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 wiped. After cooling it is weighed. The bottle is again cleaned and dried, and the operations repeated with the liquid under examination instead of water. Numerous modifications of this bottle are in use. For volatile liquids, a flask provided with a long neck which carries a graduation and is fitted with a well-ground stopper is recommended. The bringing of the liquid to the mark is effected by removing the excess by means of a capillary. In many forms a thermometer forms part of the apparatus.

Another type of vessel, named the Sprengel tube or pycnometer (Gr. , dense), is shown in fig. 3. It consists of a cylindrical tube of a capacity ranging from 10 to 50 cc., provided at the upper end with a thick-walled capillary bent as shown on the left of the figure. From the bottom there leads another fine tube, bent upwards, and then at right angles so as to be at the same level as the capillary branch. This tube bears a graduation. A loop of platinum wire passed under these tubes serves to suspend the vessel from the balance arm. The manner of cleansing, &c., is the same as in the ordinary form. The vessel is filled by placing the capillary in a vessel containing the liquid and gently aspirating. Care must be taken that no air bubbles are enclosed. The liquid is adjusted to the mark by withdrawing any excess from the capillary end by a strip of bibulous paper or by a capillary tube. Many variations of this apparatus are in use; in one of the commonest there are two cylindrical chambers, joined at the bottom, and each provided at the top with fine tubes bent at right angles; sometimes the inlet and outlet tubes are provided with caps.

The specific gravity bottle may be used to determine the relative density of a solid which is available in small fragments, and is insoluble in the standard liquid. The method involves three operations:—(1) weighing the solid in air (W), (2) weighing the specific gravity bottle full of liquid (W1), (3) weighing the bottle containing the solid and filled up with liquid (W2). It is readily seen that W + W1 - W2 is the weight of the liquid displaced by the solid, and therefore is the weight of an equal volume of liquid; hence the relative density is W/(W + W1 - W2).

The determination of the absolute densities of gases can only be effected with any high degree of accuracy by a development of this method. As originated by Regnault, it consisted in filling a large glass globe with the gas by alternately exhausting with an air-pump and admitting the pure and dry gas. The flask was then brought to 0° by immersion in melting ice, the pressure of the gas taken, and the stop-cock closed. The flask is removed from the ice, allowed to attain the temperature of the room, and then weighed. The flask is now partially exhausted, transferred to the cooling bath, and after standing the pressure of the residual gas is taken by a manometer. The flask is again brought to room-temperature, and re-weighed. The difference in the weights corresponds to the volume of gas at a pressure equal to the difference of the recorded pressures. The volume of the flask is determined by weighing empty and filled with water. This method has been refined by many experimenters, among whom we may notice Morley and Lord Rayleigh. Morley determined the densities of hydrogen and oxygen in the course of his classical investigation of the composition of water. The method differed from Regnault’s inasmuch as the flask was exhausted to an almost complete vacuum, a performance rendered possible by the high efficiency of the modern air-pump. The actual experiment necessitates the most elaborate precautions, for which reference must be made to Morley’s original papers in the Smithsonian Contributions to Knowledge (1895), or to M. Travers, The Study of Gases. Lord Rayleigh has made many investigations of the absolute densities of gases, one of which, namely on atmospheric and artificial nitrogen, undertaken in conjunction with Sir William Ramsay, culminated in the discovery of (q.v.). He pointed out in 1888 (Proc. Roy. Soc. 43, p. 361) an important correction which had been overlooked by previous experimenters with Regnault’s method, viz. the change in volume of the experimental globe due to shrinkage under diminished pressure; this may be experimentally determined and amounts to between 0.04 and 0.16% of the volume of the globe.

Related to the determination of the density of a gas is the determination of the density of a vapour, i.e. matter which at ordinary temperatures exists as a solid or liquid. This subject owes its importance in modern chemistry to the fact that the vapour density, when hydrogen is taken as the standard, gives perfectly definite information as to the molecular condition of the compound, since twice the vapour density equals the molecular weight of the compound. Many methods have been devised. In historical order we may briefly enumerate the following:—in 1811, Gay-Lussac volatilized a weighed quantity of liquid, which must be readily volatile, by letting it rise up a short tube containing mercury and standing inverted in a vessel holding the same metal. This method was developed by Hofmann in 1868, who replaced the short tube of Gay-Lussac by an ordinary barometer tube, thus effecting the volatilization in a Torricellian vacuum. In 1826 Dumas devised a method suitable for substances of high boiling-point; this consisted in its essential point in vaporizing the substance in a flask made of suitable material, sealing it when full of vapour, and weighing. This method is very tedious in detail. H. Sainte-Claire Deville and L. Troost made it available for specially high temperatures by employing porcelain vessels, sealing them with the oxyhydrogen blow-pipe, and maintaining a constant temperature by a vapour bath of mercury (350°), sulphur (440°), cadmium (860°) and zinc (1040°). In 1878 Victor Meyer devised his air-expulsion method.

Before discussing the methods now used in detail, a summary of the conclusions reached by Victor Meyer in his classical investigations in this field as to the applicability of the different methods will be given:

(1) For substances which do not boil higher than 260° and have vapours stable for 30° above the boiling-point and which do not react on mercury, use Victor Meyer’s “mercury expulsion method.”

(2) For substances boiling between 260° and 420°, and which do not react on metals, use Meyer’s “Wood’s alloy expulsion method.”

(3) For substances boiling at higher temperatures, or for any substance which reacts on mercury, Meyer’s “air expulsion method” must be used. It is to be noted, however, that this method is applicable to substances of any boiling-point (see below).

(4) For substances which can be vaporized only under diminished pressure, several methods may be used. (a) Hofmann’s is the best if the substance volatilizes at below 310°, and does not react on mercury; otherwise (b) Demuth and Meyer’s, Eykman’s, Schall’s, or other methods may be used.

1. Meyer’s “Mercury Expulsion” Method.—A small quantity of the substance is weighed into a tube, of the form shown in fig. 4, which has a capacity of about 35 cc., provided with a capillary tube at the top, and a bent tube about 6 mm. in diameter at the bottom. The vessel is completely filled with mercury, the capillary sealed, and the vessel weighed. The vessel is then lowered into a jacket containing vapour at a known temperature which is sufficient to volatilize the substance. Mercury is expelled, and when this expulsion ceases, the vessel is removed, allowed to cool, and weighed. It is necessary to determine the pressure exerted on the vapour by the mercury in the narrow limb; this is effected by opening the capillary and inclining the tube until the mercury just reaches the top of the narrow tube; the difference between the height of the mercury in the wide tube and the top of the narrow tube represents the pressure due to the mercury column, and this must be added to the barometric pressure in order to deduce the total pressure on the vapour.

The result is calculated by means of the formula: $\textstyle D = \frac{W(1 + \alpha t) \times 7,980,000} {(p + p_1 - s)[m\{1 + \beta(t - t_0)\} - m_1\{1 + \gamma(t - t_0)\}](1 + \gamma t)},$ in which W = weight of substance taken; t = temperature of vapour bath; = 0.00366 = temperature coefficient of gases; p = barometric pressure; p1 = height of mercury column in vessel; s = vapour tension of mercury at t°; m = weight of mercury contained in the vessel; m1 = weight of mercury left in vessel after heating;  = coefficient of expansion of glass = .0000303;  = coefficient of expansion of mercury = 0.00018 (0.00019 above 240°) (see Ber. 1877, 10, p. 2068; 1886, 19, p. 1862).

2. Meyer’s Wood’s Alloy Expulsion Method.—This method is a modification of the one just described. The alloy used is composed of 15 parts of bismuth, 8 of lead, 4 of tin and 3 of cadmium; it melts at 70°, and can be experimented with as readily as mercury. The cylindrical vessel is replaced by a globular one, and the pressure on the vapour due to the column of alloy in the side tube is readily reduced to millimetres of mercury since the specific gravity of the alloy at the temperature of boiling sulphur, 444° (at which the apparatus is most frequently used), is two-thirds of that of mercury (see Ber. 1876, 9, p. 1220).

3. Meyer’s Air Expulsion Method.—The simplicity, moderate accuracy, and adaptability of this method to every class of substance which can be vaporized entitles it to rank as one of the most potent methods in analytical chemistry; its invention is indissolubly connected with the name of Victor Meyer, being termed “Meyer’s method” to the exclusion of his other original methods. It consists in determining the air expelled from a vessel by the vapour of a given quantity of the substance. The apparatus is shown in fig. 5. A long tube (a) terminates at the bottom in a cylindrical chamber of about 100-150 cc. capacity. The top is fitted with a rubber stopper, or in some forms with a stop-cock, while a little way down there is a bent delivery tube (b). To use the apparatus, the long tube is placed in a vapour bath (c) of the requisite temperature, and after the air within the tube is in equilibrium, the delivery tube is placed beneath the surface of the water in a pneumatic trough, the rubber stopper pushed home, and observation made as to whether any more air is being expelled. If this be not so, a graduated tube (d) is filled with water, and inverted over the delivery tube. The rubber stopper is removed and the experimental substance introduced, and the stopper quickly replaced to the same extent as before. Bubbles are quickly disengaged and collect in the

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title: Folk-Lore/Volume 4/Folk-lore in Wills


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Rh deeds similar to them, and quite as atrocious, have been and probably are enacted daily. That we can occupy "new country" without coming into collision with the natives is scarcely to be expected until "the lion lies down with the lamb." That a few white men will be killed, and a great many blacks "dispersed," is a certainty; but we must devise some more humane system than the present, which is simply extermination; and if niggers must be shot, why, let them be shot by responsible persons who will probably reduce the bloodshed to a minimum, and be careful that the guilty parties are "dispersed," not innocent camps of natives; which, besides being barbarous, leads to much loss of life on the part of inoffensive whites.—Yours, &c., Natal Downs, July 3. Queenslander, July 24, 1880.

,—Having read many articles in your paper for and against the aborigines, the bitter complaints against the officers of police (some of which are but too painfully true), I confess all my sympathies are towards the natives, who are the weaker, and as yet quite unprotected. But in condemning the actions of the Native police force many forget that some such force was at one time a necessity, and even now in the outlying districts some protection in some manner is still requisite. It is a most intricate and difficult question to legislate upon, and it will be a lasting disgrace upon the Government if, when Parliament meets, careful and humane means are not taken to preserve and better the condition of those of the blacks who remain. It will be a work of time and patience to devise schemes for their welfare; no general law or code of laws can be of general benefit, for what would work well in one district would fail in another. I think in the first place the Government should immediately issue circulars to officers of detachments of police to use all their power towards the preservation of law, order, and humanity until Parliament shall have had time to enquire into the conflicting surroundings, and legislate in the interests of this fine but unfortunate race. But Government measures will but only partially benefit them, unless a warmer and more active interest be taken by those who are brought in contact with them like myself. I plead for the blacks; all my sympathies are with them. I have spent over a quarter of a century amongst them, have employed them and studied their character, and have come to the conclusion that no general plan or scheme for their advancement will be practicable. It will require careful investigation and much anxious thought to decide upon proper plans. In the meantime, it is to you, my neighbors, and to me, when the opportunities present themselves, to devote stone time and trouble to their moral and intellectual culture, both by precept and example; try it some of you, my bush friends, you will find it morally healthful and invigorating. Your interest in the cause will expand and grow, and you will find that in attempting to assist the needy you have brought, down a blessing upon yourselves. Much, very much, may be done in many ways, by ladies residing in the bush, to save those little black ones from vice and ruin. Strive then for the reward, "Inasmuch as ye have done it unto one of the least of these my brethren, ye have done it unto me."—Your, &c., June, 1880. —Queenslander, August, 1880.

,—I have read the article in your issue of June 12 on the above subject, signed "North Gregory." As a resident in the northern districts of this colony since 1848, and a pioneer squatter nearly all that time, I have had considerable experience amongst blacks, the wildest of them. I may also say I know a little of the way in which Native Police affairs are conducted—so much that I think myself justified in expressing contra ideas to those of "North Gregory" in many particulars. His argument to the effect that Native Police officers find the dispersing business a most painful and disagreeable duty, and one never to have recourse to unless under great provocation, is simply absurd imagery. I maintain that the aborigines are shot down indiscriminately for the most simple offences, and in many instances for no cause. If dispersing is to the officers a disagreeable duty, why do they shoot down their own troopers occasionally? I could mention the names of many good boys that have been in my employ who afterwards joined the police, to be shot down and left where they fell for the crows and dingoes to feed upon. In one case I called an inquiry, and during the inquiry was told by the P.M. at Townsville that I should not interfere

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 graduated tube. Solids may be directly admitted to the tube from a weighing bottle, while liquids are conveniently introduced by means of small stoppered bottles, or, in the case of exceptionally volatile liquids, by means of a bulb blown on a piece of thin capillary tube, the tube being sealed during the weighing operation, and the capillary broken just before transference to the apparatus. To prevent the bottom of the apparatus being knocked out by the impact of the substance, a layer of sand, asbestos or sometimes mercury is placed in the tube. To complete the experiment, the graduated tube containing the expelled air is brought to a constant and determinate temperature and pressure, and this volume is the volume which the given weight of the substance would occupy if it were a gas under the same temperature and pressure. The vapour density is calculated by the following formula: $\mbox{D} = \frac{\mbox{W}(1 + \alpha t) \times 587,780}{(p - s)\mbox{V}}$|undefined in which W = weight of substance taken, V = volume of air expelled, = 1/273 = .003665, t and p = temperature and pressure at which expelled air is measured, and s = vapour pressure of water at t°. By varying the material of the bulb, this apparatus is rendered available for exceptionally high temperatures. Vapour baths of iron are used in connexion with boiling anthracene (335°), anthraquinone (368°), sulphur (444°), phosphorus pentasulphide (518°); molten lead may also be used. For higher temperatures the bulb of the vapour density tube is made of porcelain or platinum, and is heated in a gas furnace.

(4a) Hofmann’s Method.—Both the modus operandi and apparatus employed in this method particularly recommend its use for substances which do not react on mercury and which boil in a vacuum at below 310°. The apparatus (fig. 6) consists of a barometer tube, containing mercury and standing in a bath of the same metal, surrounded by a vapour jacket. The vapour is circulated through the jacket, and the height of the mercury read by a cathetometer or otherwise. The substance is weighed into a small stoppered bottle, which is then placed beneath the mouth of the barometer tube. It ascends the tube, the substance is rapidly volatilized, and the mercury column is depressed; this depression is read off. It is necessary to know the volume of the tube above the second level; this may most efficiently be determined by calibrating the tube prior to its use. Sir T. E. Thorpe employed a barometer tube 96 cm. long, and determined the volume from the closed end for a distance of about 35 mm. by weighing in mercury; below this mark it was calibrated in the ordinary way so that a scale reading gave the volume at once. The calculation is effected by the following formulae:— $\mbox{D} = \frac{760w(1 + 0.003665t)}{0.0012934 \times \mbox{V} \times \mbox{B}}$

$\mbox{B} = \frac{h}{1 + 0.00018t_1} - \left(\frac{h_1}{1 + 0.00018t_2} - \frac{h_2}{1 + 0.00018t} + s \right),$|undefined in which w = weight of substance taken; t = temperature of vapour jacket; V = volume of vapour at t; h = height of barometer reduced to 0°; t1 = temperature of air; h1 = height of mercury column below vapour jacket; t2 = temperature of mercury column not heated by vapour; h2 = height of mercury column within vapour jacket; s = vapour tension of mercury at t°. The vapour tension of mercury need not be taken into account when water is used in the jacket.

(4b) Demuth and Meyer’s Method.—The principle of this method is as follows:—In the ordinary air expulsion method, the vapour always mixes to some extent with the air in the tube, and this involves a reduction of the pressure of the vapour. It is obvious that this reduction may be increased by accelerating the diffusion of the vapour. This may be accomplished by using a vessel with a somewhat wide bottom, and inserting the substance so that it may be volatilized very rapidly, as, for example, in tubes of Wood’s alloy, and by filling the tube with hydrogen. (For further details see Ber. 23, p. 311.) We may here notice a modification of Meyer’s process in which the increase of pressure due to the volatilization of the substance, and not the volume of the expelled air, is measured. This method has been developed by J. S. Lumsden (Journ. Chem. Soc. 1903, 83, p. 342), whose apparatus is shown diagrammatically in fig. 7. The vaporizing bulb A has fused about it a jacket B, provided with a condenser c. Two side tubes are fused on to the neck of A: the lower one leads to a mercury manometer M, and to the air by means of a cock C; the upper tube is provided with a rubber stopper through which a glass rod passes—this rod serves to support the tube containing the substance to be experimented upon, and so avoids the objection to the practice of withdrawing the stopper of the tube, dropping the substance in, and reinserting the stopper. To use the apparatus, a liquid of suitable boiling-point is placed in the jacket and brought to the boiling-point. All parts of the apparatus are open to the air, and the mercury in the manometer is adjusted so as to come to a fixed mark a. The substance is now placed on the support already mentioned, and the apparatus closed to the air by inserting the cork at D and turning the cock C. By turning or withdrawing the support the substance enters the bulb; and during its vaporization the free limb of the manometer is raised so as to maintain the mercury at a. When the volatilization is quite complete, the level is accurately adjusted, and the difference of the levels of the mercury gives the pressure exerted by the vapour. To calculate the result it is necessary to know the capacity of the apparatus to the mark a, and the temperature of the jacket.

Methods depending on the Principles of Hydrostatics.—Hydrostatical principles can be applied to density determinations in four typical ways: (1) depending upon the fact that the heights of liquid columns supported by the same pressure vary inversely as the densities of the liquids; (2) depending upon the fact that a body which sinks in a liquid loses a weight equal to the weight of liquid which it displaces; (3) depending on the fact that a body remains suspended, neither floating nor sinking, in a liquid of exactly the same density; (4) depending on the fact that a floating body is immersed to such an extent that the weight of the fluid displaced equals the weight of the body.

1. The method of balancing columns is of limited use. Two forms are recognized. In one, applicable only to liquids which do not mix, the two liquids are poured into the limbs of a U tube. The heights of the columns above the surface of junction of the liquids are inversely proportional to the densities of the liquids. In the second form, named after Robert Hare (1781–1858), professor of chemistry at the university of Pennsylvania, the liquids are drawn or aspirated up vertical tubes which have their lower ends placed in reservoirs containing the different liquids, and their upper ends connected to a common tube which is in communication with an aspirator for decreasing the pressure within the vertical tubes. The heights to which the liquids rise, measured in each case by the distance between the surfaces in the reservoirs and in the tubes, are inversely proportional to the densities.

2. The method of “hydrostatic weighing” is one of the most important. The principle may be thus stated: the solid is weighed in air, and then in water. If W be the weight in air, and W1 the weight in water, then W1 is always less than W, the difference W − W11 representing the weight of the water displaced, i.e. the weight of a volume of water equal to that of the solid. Hence W/(W − W1) is the relative density or specific gravity of the body. The principle is readily adapted to the determination of the relative densities of two liquids, for it is obvious that if W be the weight of a solid body in air, W1 and W2 its weights when immersed in the liquids, then W − W1 and W − W2 are the weights of equal volumes of the liquids, and therefore the relative density is the quotient (W − W1)/(W − W2). The determination in the case of solids lighter than water is effected by the introduction of a sinker, i.e. a body which when affixed to the light solid causes it to sink. If W be the weight of the experimental solid in air, w the weight of the sinker in water, and W1 the weight of the solid plus sinker in water, then the relative density is given by W/(W + w − W1). In practice the solid or plummet is suspended from the balance arm by a fibre—silk, platinum, &c.—and carefully weighed. A small stool is then placed over the balance pan, and on this is placed a beaker of distilled water so that the solid is totally immersed. Some balances are provided with a “specific gravity pan,” i.e. a pan with short suspending arms, provided with a hook at the bottom to which the fibre may be attached; when this is so, the stool is unnecessary. Any air bubbles are removed from the surface of the body by brushing with a camel-hair brush; if the solid be of a porous nature it is desirable to boil it for some time in water, thus expelling the air from its interstices. The weighing is conducted in the usual way by vibrations, except when the weight be small; it is then advisable to bring the pointer to zero, an operation rendered necessary by the damping due to the adhesion of water to the fibre. The temperature and pressure of the air and water must also be taken.

There are several corrections of the formula = W/(W − W1) necessary to the accurate expression of the density. Here we can only summarize the points of the investigation. It may be assumed that the weighing is made with brass weights in air at t° and p mm. pressure. To determine the true weight in vacuo at 0°, account must be taken of the different buoyancies, or losses of true weight, due to the different volumes of the solids and weights. Similarly in the case of the weighing in water, account must be taken of the buoyancy of the weights, and also, if absolute densities be required, of the density of water at the temperature of the experiment. In a form of great accuracy the absolute density (0°/4°) is given by (0°/4°) = (W − W1)/(W − W1), in which W is the weight of the body in air at t° and p mm. pressure, W1 the weight in water, atmospheric conditions remaining very nearly the same; is the density of the water in which the body is weighed,  is (1 + t°) in which  is the coefficient of cubical expansion of the body, and  is the density of the air at t°, p mm. Less accurate formulae are  =  W/(W − W1), the factor involving the density of the air, and the coefficient of the expansion of the solid being disregarded, and  = W/(W − W1), in which the density of water is taken as unity. Reference may be made to J. Wade and R. W. Merriman, ''Journ. Chem. Soc.'' 1909, 95, p. 2174.

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  The determination of the density of a liquid by weighing a plummet in air, and in the standard and experimental liquids, has been put into a very convenient laboratory form by means of the apparatus known as a Westphal balance (fig. 8). It consists of a steelyard mounted on a fulcrum; one arm carries at its extremity a heavy bob and pointer, the latter moving along a scale affixed to the stand and serving to indicate when the beam is in its standard position. The other arm is graduated in ten divisions and carries riders—bent pieces of wire of determined weights—and at its extremity a hook from which the glass plummet is suspended. To complete the apparatus there is a glass jar which serves to hold the liquid experimented with. The apparatus is so designed that when the plummet is suspended in air, the index of the beam is at the zero of the scale; if this be not so, then it is adjusted by a levelling screw. The plummet is now placed in distilled water at 15°, and the beam brought to equilibrium by means of a rider, which we shall call 1, hung on a hook; other riders are provided, th and th respectively of 1. To determine the density of any liquid it is only necessary to suspend the plummet in the liquid, and to bring the beam to its normal position by means of the riders; the relative density is read off directly from the riders.

3. Methods depending on the free suspension of the solid in a liquid of the same density have been especially studied by Retgers and Gossner in view of their applicability to density determinations of crystals. Two typical forms are in use; in one a liquid is prepared in which the crystal freely swims, the density of the liquid being ascertained by the pycnometer or other methods; in the other a liquid of variable density, the so-called “diffusion column,” is prepared, and observation is made of the level at which the particle comes to rest. The first type is in commonest use; since both necessitate the use of dense liquids, a summary of the media of most value, with their essential properties, will be given.

Acetylene tetrabromide, C2H2Br4, which is very conveniently prepared by passing acetylene into cooled bromine, has a density of 3.001 at 6° C. It is highly convenient, since it is colourless, odourless, very stable and easily mobile. It may be diluted with benzene or toluene.

Methylene iodide, CH2I2, has a density of 3.33, and may be diluted with benzene. Introduced by Brauns in 1886, it was recommended by Retgers. Its advantages rest on its high density and mobility; its main disadvantages are its liability to decomposition, the originally colourless liquid becoming dark owing to the separation of iodine, and its high coefficient of expansion. Its density may be raised to 3.65 by dissolving iodoform and iodine in it.

Thoulet’s solution, an aqueous solution of potassium and mercuric iodides (potassium iodo-mercurate), introduced by Thoulet and subsequently investigated by V. Goldschmidt, has a density of 3.196 at 22.9°. It is almost colourless and has a small coefficient of expansion; its hygroscopic properties, its viscous character, and its action on the skin, however, militate against its use. A. Duboin (Compt. rend., 1905, p. 141) has investigated the solutions of mercuric iodide in other alkaline iodides; sodium iodo-mercurate solution has a density of 3.46 at 26°, and gives with an excess of water a dense precipitate of mercuric iodide, which dissolves without decomposition in alcohol; lithium iodo-mercurate solution has a density of 3.28 at 25.6°; and ammonium iodo-mercurate solution a density of 2.98 at 26°.

Rohrbach’s solution, an aqueous solution of barium and mercuric iodides, introduced by Carl Rohrbach, has a density of 3.588.

Klein’s solution, an aqueous solution of cadmium borotungstate, 2Cd(OH)2·B2O3·9WO3·16H2O, introduced by D. Klein, has a density up to 3.28. The salt melts in its water of crystallization at 75°, and the liquid thus obtained goes up to a density of 3.6. Silver-thallium nitrate, TlAg(NO3)2, introduced by Retgers, melts at 75° to form a clear liquid of density 4.8; it may be diluted with water.

The method of using these liquids is in all cases the same; a particle is dropped in; if it floats a diluent is added and the mixture well stirred. This is continued until the particle freely swims, and then the density of the mixture is determined by the ordinary methods (see ).

In the “diffusion column” method, a liquid column uniformly varying in density from about 3.3 to 1 is prepared by pouring a little methylene iodide into a long test tube and adding five times as much benzene. The tube is tightly corked to prevent evaporation, and allowed to stand for some hours. The density of the column at any level is determined by means of the areometrical beads proposed by Alexander Wilson (1714–1786), professor of astronomy at Glasgow University. These are hollow glass beads of variable density; they may be prepared by melting off pieces of very thin capillary tubing, and determining the density in each case by the method just previously described. To use the column, the experimental fragment is introduced, when it takes up a definite position. By successive trials two beads, of known density, say d1, d2, are obtained, one of which floats above, and the other below, the test crystal; the distances separating the beads from the crystal are determined by means of a scale placed behind the tube. If the bead of density d1 be at the distance l1 above the crystal, and that of d2 at l2 below, it is obvious that if the density of the column varies uniformly, then the density of the test crystal is (d1l2 + d2l1)/(l1 + l2).

Acting on a principle quite different from any previously discussed is the capillary hydrometer or staktometer of Brewster, which is based upon the difference in the surface tension and density of pure water, and of mixtures of alcohol and water in varying proportions.

If a drop of water be allowed to form at the extremity of a fine tube, it will go on increasing until its weight overcomes the surface tension by which it clings to the tube, and then it will fall. Hence any impurity which diminishes the surface tension of the water will diminish the size of the drop (unless the density is proportionately diminished). According to Quincke, the surface tension of pure water in contact with air at 20° C. is 81 dynes per linear centimetre, while that of alcohol is only 25.5 dynes; and a small percentage of alcohol produces much more than a proportional decrease in the surface tension when added to pure water. The capillary hydrometer consists simply of a small pipette with a bulb in the middle of the stem, the pipette terminating in a very fine capillary point. The instrument being filled with distilled water, the number of drops required to empty the bulb and portions of the stem between two marks m and n (fig. 9) on the latter is carefully counted, and the experiments repeated at different temperatures. The pipette having been carefully dried, the process is repeated with pure alcohol or with proof spirits, and the strength of any admixture of water and spirits is determined from the corresponding number of drops, but the formula generally given is not based upon sound data. Sir David Brewster found with one of these instruments that the number of drops of pure water was 734, while of proof spirit, sp. gr. 920, the number was 2117.

—Density and density determinations are discussed in all works on practical physics; reference may be made to B. Stewart and W. W. Haldane Gee, Practical Physics, vol. i. (1901); Kohlrausch, Practical Physics; Ostwald, Physico-Chemical Measurements. The density of gases is treated in M. W. Travers, The Experimental Study of Gases (1901); and vapour density determinations in Lassar-Cohn’s Arbeitsmethoden für organisch-chemische Laboratorien (1901), and Manual of Organic Chemistry (1896), and in H. Biltz, Practical Methods for determining Molecular Weights (1899).

 DENTATUS, MANIUS CURIUS, Roman general, conqueror of the Samnites and Pyrrhus, king of Epirus, was born of humble parents, and was possibly of Sabine origin. He is said to have been called Dentatus because he was born with his teeth already grown (Pliny, Nat. Hist. vii. 15). Except that he was tribune of the people, nothing certain is known of him until his first consulship in 290 when, in conjunction with his colleague P. Cornelius Rufinus, he gained a decisive victory over the Samnites, which put an end to a war that had lasted fifty years. He also reduced the revolted Sabines to submission; a large portion of their territory was distributed among the Roman citizens, and the most important towns received the citizenship without the right of voting for magistrates (civitas sine suffragio). With the proceeds of the spoils of the war Dentatus cut an artificial channel to carry off the waters of Lake Velinus, so as to drain the valley of Reate. In 275, after Pyrrhus had returned from Sicily to Italy, Dentatus (again consul) took the field against him. The decisive engagement took place near Beneventum in the Campi Arusini, and resulted in the total defeat of Pyrrhus. Dentatus celebrated a magnificent triumph, in which for the first time a number of captured elephants were exhibited. Dentatus was consul for the third time in 274, when he finally crushed the Lucanians and Samnites, and censor in 272. In the latter capacity he began to build an aqueduct to carry the waters of the Anio into the city, but died (270) before its completion. Dentatus was looked upon as a model of old Roman simplicity and frugality. According to the well-known anecdote, when the Samnites sent ambassadors with costly presents to induce him to exercise his influence on their behalf in the senate, they found

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Portal:McLoughlin Brothers

Aunt Mary's Little Series

 * The Crooked Man And Other Rhymes
 * Five Little Pigs

Familiar Series

 * The Three Bears

Little Folks Series

 * The Five Little Pigs

Natural History Series

 * Dog of St. Bernard, and other stories
 * The Horse, and other stories
 * The Goat
 * The Swan
 * The Lion, and other tales
 * The Tiger

Uncle Dick's Series

 * Nursery Rhymes

Uncle John's Drolleries

 * Miss Mouser's tea party

Uncle Toby's Series

 * Dame Duck's lecture
 * Naughty Puppies

...In Words of One Syllable

 * The Swiss Family Robinson, In Words of One Syllable

 * The Ark alphabet

title: Portal:McLoughlin Brothers


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Page:Folk-lore - A Quarterly Review. Volume 4, 1893.djvu/521

 MELANESIAN FOLK-TALES.

(Sta. Cruz.)

EFORE Lata was born, an eel foretold that he would eat it. After his birth, his father caught the eel, cut off its tail, and gave it to the child to suck. When Lata was two days old, his father and mother went kite-fishing, and left the child covered under a wooden bowl. The parents were blown away out to sea, and the child grew by himself alone under the bowl. When he was grown, he saw the light under the edge of the bowl, threw it off, and came out into the light. Then he made himself toy canoes with larger and larger leaves in succession, till he made one in which he could sail about, and then, seeing a tree, began to cut it down for a real canoe. Every day, as he ceased working, one Ginota came and replaced what he had cut. At last he was unable to do so, because a chip had fallen into Lata's bag; so he waited till Lata came back in the morning, when the rattling of the chip in his bag betrayed him, and the two agreed to work together. The tree was properly shaped and carried down to the village, the various parts and sails made and fitted, and the proper feasts given to the people. When the canoe was launched, Lata's mother cautioned him against certain fish which would jump into it and break it; but these he caught in a net and brought back for her to cook. Next she warned him against a shark, and this he killed with a sharp stake. Then she warned him against a giant clam, and in his next voyage he found his canoe being carried by a current into the jaws of an enormous shell. He saved himself by thrusting an upright


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 510 log between the jaws, dug out the fish, and carried it to his mother to cook. Next she cautioned him against a bird which would swoop upon him and pierce him with its beak. He saved himself from this by setting up a banana-stalk in the canoe, while he hid himself below; the bird swooped and fastened its beak in the banana, Lata seized it, broke its wings, and took it to his mother to cook. His mother then warned him of one thing more, a huge sea monster, like a whale, which swallowed down canoes. Into this monster's stomach Lata was carried by a current which sucked in his canoe with sail standing; and in it he found a man and woman who had eaten their clothes and their hair for hunger. To feed them he made a fire with the wrecks of the canoes lying about, and cut off some of the whale's liver to roast. Lavalu, the monster, cried out that he was killing him; and Lata answered, that if he wished to live he must carry him home. This he did, making so high a tide that he was stranded on the shore of Sta. Cruz. Lata dragged out his canoe, and gave Lavalu over to the crabs. His mother next warned him of a tide that would break his canoe; but he took out hermit crabs, which bit the waves, so that he passed through safely. Then his mother warned him of the Tapakola at Nupani. He sailed, therefore, immediately to Nupani, and was invited by the Tapakola to her house, where she sat in ambush for him over the only door left open, intending to kill him as he stooped to enter. He pushed open another door, and came in unhurt. All the night she watched to kill him when asleep, but, though he slept, he had covered his eyes with shining shells, which made him appear to be awake. In the morning he invited Tapakola to come with him in his canoe, and drowned her on the voyage home.

The next adventure of Lata, in which he deceived a snake, is not of much interest.

After that his mother bade him remember that there remained the great Land Crab at Netepa (Taumako in


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 Rh the Duff group). He sailed thither, and was invited by the Crab into its house, where, as before with the Tapakola, he escaped the ambush set for him by pushing open one of the shut doors. Then Lata, seeing the skulls of men devoured by the Crab, painted himself red, white, and black, so much to the Crab's admiration that it desired to know how it could be done. He undertook to produce the same beautiful effect, and persuaded the Crab to mount on the stage over the hearth, and to sit there while he lighted the fire and heaped on wood. The Crab turned red with the heat—the first stage, as Lata assured it, in the beautifying process; then the claws dropped off, and the Crab died. One claw he ate, the other he took home to his mother.

His further adventures, as he sailed about escaping from dangers and deceiving enemies, are very numerous.

.

(Saddle Isle, Banks' Group.)

A party of boys were up in a tree eating the fruit. All went off but two brothers, the elder of whom warned the younger not to throw the kernels on the ground, lest that should happen of which their father had warned them; but he let a fruit drop himself, and immediately appeared under the tree Hole-in-his-Back himself, and begged the boys to throw him down some fruit. At first they were afraid, but after a while threw him down a bunch, which he caught in the hole in his back as in a sack. In this way he received all the fruit on the tree; then he begged them to come down to him, and, with much fear, they consented. He took them to his abode, a cave without an entrance; and, when he came to it, they heard him say: "Close, cave! be open, cave!" The cave opened, and they went in. He bade them stay while he went to get them food, and, as he went out, they heard him say: "Open, cave! be close, cave!" and the mouth of the cave


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 512 shut close upon them. On his return, they heard him open the cave's mouth with the same words, and he brought out of the hole in his back, in which he had stowed them, a pig and yams, which they cooked, and he ate raw. Thus they lived in the cave, while their parents and friends in the village counted the days for their death, ate the death-meals, and then forgot them. One day, when he was longer absent than usual, they agreed to try whether the cave would open and shut for them, as it did for him, at the sound of the same words, and they found that it would.

Now there was one part of the cave which Hole-in-his-Back always, when he went out, forbade them to go near; and here, when at last they ventured to approach, they found a heap of conch trumpets; and this was the reason why he had forbidden them to go there, because, being a Vui, he was afraid of the sound of a conch-shell trumpet. The boys began to plan a way of escape, and accordingly prepared for themselves tamate dresses, in which they proposed to show themselves in the village blowing shell trumpets, after the fashion of the tamates whose dress they were assuming. Accordingly, when all was ready, they put on each his tamate hat, and took each his conch trumpet in his hand, and waited for the return of Hole-in-his-Back with his pig and food. They heard him coming; they heard him saying: "Close, cave! be open, cave!" and, as the cave's mouth opened, before he could say a word, they ran out blowing their trumpets. He ran away affrighted, and they chased him into the village, through the village to the beach and on to the reef, blowing their trumpets as they ran; from the reef he leapt into the sea, the water poured into the hollow in his back, and he was drowned. The boys returned and made themselves known again to their parents in the village.

2em


text: Index:U.S. Department of the Interior Annual Report 1883.djvu


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Portal:Meteoroids

Works

 * Chapter 15: Navigational Astronomy from The American Practical Navigator, 1802 by the United States government
 * Chapter 1: The Romance of the Heavens from The Outline of Science, by John Arthur Thomson

Journal articles

 * "An Account of several fiery Meteors seen in North America" by John Winthrop in Philosophical Transactions, volume 54 (1764)
 * Astro-Meteorology by Daniel Kirkwood as it appeared in the July 1872 Popular Science Monthly
 * The August and November Meteors by Heinrich Schellen as it appeared in the August 1872 Popular Science Monthly
 * On Meteoric Stones by Nevil Story Maskelyne as it appeared in the November 1872 Popular Science Monthly
 * The Great Iowa Meteor by Gustavus Detlef Hinrichs as it appeared in the September 1875 Popular Science Monthly
 * The Story of the November Meteors by George Johnstone Stoney as it appeared in the August 1879 Popular Science Monthly
 * Expected Meteoric Display by Richard Anthony Proctor as it appeared in the December 1879 Popular Science Monthly
 * The August Meteors by William Frederick Denning as it appeared in the December 1880 Popular Science Monthly
 * The Meteors of November 13th-15th by Daniel Kirkwood as it appeared in the February 1881 Popular Science Monthly
 * The Discovery of Organic Remains in Meteoric Stones by Francis Birgham as it appeared in the November 1881 Popular Science Monthly
 * A Singular Meteoric Phenomenon, by George Belknap as it appeared in the February 1883 Science
 * Astro-Meteorology, Kirkwood, Daniel (1872) Popular Science Monthly
 * The August and November Meteors, Schellen, Heinrich (1872)Popular Science Monthly
 * On Meteoric Stones, Maskelyne, Nevil Story (1872) Popular Science Monthly
 * The Great Iowa Meteor, Hinrichs, Gustavus Detlef (1875) Popular Science Monthly
 * The Story of the November Meteors, Stoney, George Johnstone (1879) Popular Science Monthly
 * The August Meteors, Denning, William Frederick (1880) Popular Science Monthly
 * The Meteors of November 13th-15th, Kirkwood, Daniel (1881) Popular Science Monthly
 * The Discovery of Organic Remains in Meteoric Stones, Birgham, Francis (1881) Popular Science Monthly

Reference

 * Meteors from the The New Student's Reference Work

Fiction

 * The Colour Out of Space, 1927 by H. P. Lovecraft

title: Portal:Meteoroids


text: Index:U.S. Department of the Interior Annual Report 1885.djvu


text: Portal talk:Geology

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text: Portal talk:Meteoroids

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Page:EB1911 - Volume 08.djvu/65

 him sitting on the hearth and preparing his simple meal of roasted turnips. He refused their gifts, saying that earthen dishes were good enough for him, adding that he preferred ruling those who possessed gold to possessing it himself. It is also said that he died so poor that the state was obliged to provide dowries for his daughters. But these and similar anecdotes must be received with caution, and it should be remembered that what was a competence in his day would have been considered poverty by the Romans of later times.

 DENTIL (from Lat. dens, a tooth), in architecture, a small tooth-shaped block used as a repeating ornament in the bed-mould of a cornice. Vitruvius (iv. 2) states that the dentil represents the end of a rafter (asser); and since it occurs in its most pronounced form in the Ionic temples of Asia Minor, the Lycian tombs and the porticoes and tombs of Persia, where it represents distinctly the reproduction in stone of timber construction, there is but little doubt as to its origin. The earliest example is that found on the tomb of Darius, c. 500, cut in the rock in which the portico of his palace is reproduced. Its first employment in Athens is in the cornice of the caryatid portico or tribune of the Erechtheum (480 ). When subsequently introduced into the bed-mould of the cornice of the choragic monument of Lysicrates it is much smaller in its dimensions. In the later temples of Ionia, as in the temple of Priene, the larger scale of the dentil is still retained. As a general rule the projection of the dentil is equal to its width, and the intervals between to half the width. In some cases the projecting band has never had the sinkings cut into it to divide up the dentils, as in the Pantheon at Rome, and it is then called a dentil-band. The dentil was the chief decorative feature employed in the bed-mould by the Romans and the Italian Revivalists. In the porch of the church of St John Studius at Constantinople, the dentil and the interval between are equal in width, and the interval is splayed back from top to bottom; this is the form it takes in what is known as the “Venetian dentil,” which was copied from the Byzantine dentil in Santa Sophia, Constantinople. There, however, it no longer formed part of a bed-mould: its use at Santa Sophia was to decorate the projecting moulding enclosing the encrusted marbles, and the dentils were cut alternately on both sides of the moulding. The Venetian dentil was also introduced as a label round arches and as a string course.

 DENTISTRY (from Lat. dens, a tooth), a special department of medical science, embracing the structure, function and therapeutics of the mouth and its contained organs, specifically the teeth, together with their surgical and prosthetic treatment. (For the anatomy of the teeth see .) As a distinct vocation it is first alluded to by Herodotus (500 ). There are evidences that at an earlier date the Egyptians and Hindus attempted to replace lost teeth by attaching wood or ivory substitutes to adjacent sound teeth by means of threads or wires, but the gold fillings reputed to have been found in the teeth of Egyptian mummies have upon investigation been shown to be superficial applications of gold leaf for ornamental purposes. The impetus given to medical study in the Grecian schools by the followers of Aesculapius and especially Hippocrates (500 to 400 ) developed among the practitioners of medicine and surgery considerable knowledge of dentistry. Galen ( 131) taught that the teeth were true bones existing before birth, and to him is credited the belief that the upper canine teeth receive branches from the nerve which supplies the eye, and hence should be called “eye-teeth.” Abulcasis (10th cent. ) describes the operation by which artificial crowns are attached to adjacent sound teeth. Vesalius (1514), Ambroise Paré, J. J. Scaliger, T. Kerckring, M. Malpighi, and lesser anatomists of the same period contributed dissertations which threw some small amount of light upon the structure and functions of the teeth. The operation of transplanting teeth is usually attributed to John Hunter (1728–1793), who practised it extensively, and gave to it additional prominence by transplanting a human tooth to the comb of a cock, but the operation was alluded to by Ambroise Paré (1509–1590), and there is evidence to show that it was practised even earlier. A. von Leeuwenhoek in 1678 described with much accuracy the tubular structure of the dentine, thus making the most important contribution to the subject which had appeared up to that time. Until the latter part of the 18th century extraction was practically the only operation for the cure of toothache.

The early contributions of France exerted a controlling influence upon the development of dental practice. Urbain Hémard, surgeon to the cardinal Georges of Armagnac, whom Dr Blake (1801) calls an ingenious surgeon and a great man, published in 1582 his Researches upon the Anatomy of the Teeth, their Nature and Properties. Of Hémard, M. Fauchard says: “This surgeon had read Greek and Latin authors, whose writings he has judiciously incorporated in his own works.” In 1728 Fauchard, who has been called the father of modern dentistry, published his celebrated work, entitled Le Chirurgien Dentiste ou traité des dents. The preface contains the following statement as to the existing status of dental art and science in France, which might have been applied with equal truth to any other European country:—“The most celebrated surgeons having abandoned this branch of surgery, or having but little cultivated it, their negligence gave rise to a class of persons who, without theoretic knowledge or experience, and without being qualified, practised it at hazard, having neither principles nor system. It was only since the year 1700 that the intelligent in Paris opened their eyes to these abuses, when it was provided that those who intended practising dental surgery should submit to an examination by men learned in all the branches of medical science, who should decide upon their merits.” After the publication of Fauchard’s work the practice of dentistry became more specialized and distinctly separated from medical practice, the best exponents of the art being trained as apprentices by practitioners of ability, who had acquired their training in the same way from their predecessors. Fauchard suggested porcelain as an improvement upon bone and ivory for the manufacture of artificial teeth, a suggestion which he obtained from R. A. F. de Réaumur, the French savant and physicist, who was a contributor to the royal porcelain manufactory at Sévres. Later, Duchateau, an apothecary of St Germain, made porcelain teeth, and communicated his discovery to the Academy of Surgery in 1776, but kept the process secret. Du Bois Chémant carried the art to England, and the process was finally made public by M. Du Bois Foucou. M. Fonzi improved the art to such an extent that the Athenaeum of Arts in Paris awarded him a medal and crown (March 14, 1808).

In Great Britain the 19th century brought the dawning of dental science. The work of Dr Blake in 1801 on the anatomy of the teeth was distinctly in advance of anything previously written on the subject. Joseph Fox was one of the first members of the medical profession to devote himself exclusively to dentistry, and his work is a repository of the best practice of his time. The processes described, though comparatively crude, involve principles in use at the present time. Thomas Bell, the successor of Fox as lecturer on the structure and disease of the teeth at Guy’s Hospital, published his well-known work in 1829. About this period numerous publications on dentistry made their appearance, notably those of Koecker, Johnson and Waite, followed somewhat later by the admirable work of Alexander Nasmyth (1839). By this time Cuvier, Serres, Rousseau, Bertin, Herissant and others in France had added to the knowledge of human and comparative dental anatomy, while M. G. Retzius, of Sweden, and E. H. Weber, J. C. Rosenmüller, Schreger, J. E. von Purkinje, B. Fraenkel and J. Müller in Germany were carrying forward the same lines of research. The sympathetic nervous relationships of the teeth with other parts of the body, and the interaction of diseases of the teeth with general pathological conditions, were clearly established. Thus a scientific foundation was laid, and dentistry came to be practised as a specialty of medicine. Certain minor operations, however, such as the extraction of teeth and the stopping of caries in an imperfect way, were still practised by barbers, and the empirical practice of dentistry, especially of

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text:
The Seamstress

"How pretty you are to-day, Theresa."

"Oh, nonsense!"

"But it's true, though! that kerchief of pink crepe against your white throat."

"Oh, you're joking!"

"And your hair is as black as your eyes, did you know it?"

"You flatterer!"

"And such a slender little figure, in such a gracefully draped gown! That's an awfully pretty muslin, you know!"

"You don't say so!"

"You see I am very fond of lilac. It always was a favorite color of mine. And then it falls so prettily over a dainty shoe, when it's as tiny as yours is. My, what a cunning foot it is, to be sure! If you would put it just a trifle further out... so!"

"Well, well, listen to this!"

"I would like to have your photograph, in just that position, but looking up at me,... so!"

"What taste you have!"

"To be sure I have! And why not?"

"I'd have you know I've been photographed already."

"Indeed?"

"And by Pica-Groom."

"In the position I like?"

"Mercy on us, no! I'm in my ball-dress I had on Sunday when you met us near the gas factory."

"And nothing would induce you to look at me, Theresa! You were having such fun!"

"There were eight or nine of us!"

"Oh, surely nine, Theresa. You seemed to me the nine Muses, all in one graceful band together!"

"Oh, get along with you! You are always laughing at people and calling them names!"

"But among those trees, and going up that hill... Mount Helicon, of course..."

"Where is that?"

"Mount Helicon? Oh, it's a little beyond Torrelavega. But what I did not like about it was that Apollo who went with you."

"His name was not Pollo. He's a clerk..."

"I thought as much... I mean he seemed somewhat commonplace, while you were all so airy, fairy, beautiful!"

"There, now you're at it again! Yes, we were going to the ball at Miranda, as we do every Sunday."

"Yes, I heard the organ."

"And the man who was with us was one of the set who gets up the balls. And as he had given me tickets for all the summer dances in the garden, and if it comes handy will invite us for the winter ones, too, in the hall..."

"Yes, I know these impresarios and their friends are very gallant fellows. They pay, that you may dance all the year round, for nothing."

"Just so! And we are just as good as the ladies who do the same thing!"

"Of course you are!"

"It seems to me that the 'Cream and Flower' and the 'Organ' have no reason to envy any other dancing-place."

"Above all, in pretty faces and lively dancers!"

"As you say, it is..."

"What I said, or was just going to say is, that because you were going to a dance was no reason for not bowing on the street."

"Goodness! What would people say?"

"How do you mean that, 'What would people say'?"

"Why, that's clear enough! What would people say to your knowing us?"

"You say that with a tone..."

"No, no, not at all; but it's true, for all that."

"Nonsense! I bow to everybody on the street, and enjoy it, and above all when I meet you!"

"Thank you, but..."

"But what?"

"Well, I don't believe you, there! You're a great joker... and well, to tell the plain truth, I don't feel any confidence in you."

"Ah, there we have it! But why should you not trust me? Surely, you don't take me for a gay deceiver, do you?"

"Oh no, but the men in your set and you yourself are great gossips."

"You are hard on me, Theresa!"

"I'm sorry for it, I'm sure, but I always tell the truth. When you passed us on Sunday one of the girls and I were talking of that very thing."

"The one who was walking on your right?"

"What made you guess her?"

"Because she pleased me so much, the witty red-head!"

"So you're taken with the Anvil?"

"And why Anvil, if I may ask!"

"Stupid! That's what they call the girl."

"And why do they call her so?"

"Because her father is a blacksmith."

"Heavens! What a name!"

"And the one who was walking on my left, don't you know her name either?"

"No, my dear."

"Well, where do you keep yourself, anyway?"

"At least this will prove how unjust you were before, when you doubted my sincerity!"

"For all that I thought every one knew Beanie."

"I do not know her by that name. And how did she come by it?"

"Why, her mother sells beans in the Square."

"How atrocious!"

"Oh, we all have nicknames of that sort. And now you're beginning to see daylight, eh?"

"I assure you I am. And who has amused himself with baptizing you all in this fashion?"

"Well, when we were being taught as little girls, and then later at the dances, there's always some one who, for the sake of joking with us a bit, gives us a nickname, and as ill weeds grow apace..."

"What a notion! And among yourselves you go by these names?"

"Not a bit of it! Still, we know them, and as they are no disgrace..."

"Of course... but to return to our red-head."

"You seem to think of no one else."

"As you said you were talking about me..."

"I said that?"

"At least, you said something very like it."

"What I said was that we were talking about the way some men had of boasting about things that had never happened to them."

"I'm sure that doesn't hit me."

"No, certainly not, but some of the men you know very well."

"It may be so. And do you know, Theresa, that for some time the red-head has been putting on all sorts of airs and graces."

"Didn't I tell you!"

"Oh, I say it with no thought of injuring the girl."

"That's the way all these things are said, and then the Evil One is in it! If a girl is a little dressed up some fine day, my, how they talk! It's plain enough that you are used to hearing that a lady must spend a small fortune to present a decent appearance on the street, and as we have no income, the moment you see us spruced up a bit you think at once we have presents given us... as they should not be given. Neither the redhead nor I have anything but the twenty cents we earn by sewing at the houses where we are employed, and the cup of chocolate they give us for breakfast and supper, as you know. But we know our trade, and with two yards of tulle and six yards of dimity we make a dress that those who do not understand such things think must be worth a lot of money. Take the one I have on now... it will wear for four summers, and who knows how much longer, if water and soap and irons are still left us! So there you have it!"

"I think so, too, my dear."

"Of course, this girl is naturally showy, and has some style, and then she has a wonderful knack at cutting and sewing. She can make a ball-dress just out of old skirts..."

"I never said anything to the contrary, you know."

"And seeing her dressed for the street, as she has good looks and a pretty figure... uf! the least they think is that it was bought with bad money. And that you may know how things really are, the poor girl has to provide her father's smoking tobacco out of that same twenty cents! But of course, it's only a poor little seamstress... and so it goes on! And if I were to tell all I know... how many silk dresses rustle through these streets that have never been paid for, and how many, too, that have been paid for, without the husbands of the ladies that wear them being a bit the poorer! But they are fine ladies, and are pardoned in advance for all their sins... and so it is with other things... how many of the graceful figures you admire so much have been made with these two hands! But I guess I'd better stop right there."

"You are unkind, Theresa! What I said about the red-head was just for the sake of saying something. For the last three or four days, when she went by at noontime in the Old Square, I noticed she was more dressed than usual, and..."

"That means you go there on purpose to watch her go by."

"I won't say that I go to see her, but perhaps to see her, you, and the others, yes."

"And what do you get out of it, anyway?"

"It does my eyes good! It really does! You are so pretty, one and all of you! But I must say I am deeply shocked to notice how you all manage to pass through the Square, no matter where you come from or where you are going to."

"Well, I suppose all roads lead to Rome, don't they?... and when we leave off sewing for an hour at noon, we take half of it to see people, and get a little fresh air."

"And what a pretty friend of yours that was that stopped you this morning at the corner of the street! But she is not so stylish as you are."

"Oh, you mean a very dark girl? She's not a friend of mine... she sews for a tailor."

"Oh, I see; but as you were talking with her..."

"She was just giving me a message. And it isn't that I don't care to be friendly with some of them, but you see that we who go out to do fine sewing keep ourselves to ourselves. And don't go and think we haven't good reason to set ourselves up above them... look at the way the dressmakers treat us! My, you'd think they were doing us an honor when they bow to us on the street."

"What a wise sly-boots it is, to be sure!"

"And now I think of it, what were you saying this morning to that gentleman with whiskers, when we went by, and you were staring so?"

"So you saw me?"

"Oh, I see all I want to, and more too!"

"You are a pretty little mischief-maker, Theresa! I shall take that as a warning. Well, then, I was saying to my friend that you were all so much prettier when you went out with nothing on your head, with your hair so beautifully done up, and those fetching little kerchiefs round your necks, like the one you have on now, than when you wear a mantilla and shawl, which hide the graceful outlines."

"My eye, what a lot you see!"

"Of course we do!"

"But they don't all of them wear a mantilla."

"And you are one of the exceptions, and I warn you now, so that you may never make the mistake of putting one on."

"And where's the harm, anyway?"

"With the mantilla you would cease to be an exceedingly pretty type of the pure Santander race, and would simply be lost in the common crowd of young ladies all more or less far from chic."

"Some of my friends can wear a veil as well as anybody."

"But you see a veil is never becoming, because while it does not really cover an ugly face, it hides a pretty one, and then it requires a shawl, which conceals the figure."

"My goodness! What a lot you know about it all!"

"I am an artist, Theresa."

"And what are you driving at, after all?"

"Mere trifles. I study beauty wherever I find it."

"It seems to me that what you are studying is just pure mischief!"

"That is not true! Nor is it an argument in favor of wearing veils."

"Well, I don't like them, either, but they're the fashion. But what are you staring at so, through the window?"

"What makes you blush like that?"

"I, blush? Goodness! Perhaps you think it's because of that young fellow in the doorway over there!"

"You are defending yourself before you are accused, Theresa."

"You see, you might be fancying it was something else, and as the lad is more or less on my mind... and he's a real good fellow too."

"You are not telling me the truth, Theresa. I know him very well, and I know he would not be waiting every day at this hour, if he did not hope..."

"Has the good-for-nothing been telling you what is not true?"

"On my word of honor, we have not mentioned the subject."

"You see, that sort of thing happens so often. And now let me tell you, so you needn't go thinking something that is not true, that I do like the lad. But he is just losing his time."

"I do not understand."

"Well, a year ago he danced with me at the 'Cream and Flower.' And ever since then, I don't know how, he finds out where I am going to sew. But I am sure to meet him this way every evening when I leave off work, above all in winter, when we go out at night-fall... and that is what worries me."

"That he goes with you after dark?"

"No; that he seems to care less about going with me in the daytime."

"Then what is he about, over opposite?"

"Oh, he's waiting for me. But when we get to the corner of the street, he will make some excuse, and off he goes! And when I am at work on the Mole, or any central street, he waits for me in the same doorway, then we talk for a while, and then... each one goes off on his own hook. You see there is no real pleasure in this sort of thing, and for that reason I like my own kind better."

"And who are they?"

"Oh, the office clerks. We understand each other perfectly, and if some day,... well, you know what I mean,... it's all between poor folks. But with these fine fellows, it's a more serious affair, and woe be unto the unhappy girl who is tempted by one of them! What she has to go through with, first with him and then with the family, as if she it were who had been running after him! You know how it all comes about; it all begins in fun, and as it generally happens that the girl is foolish and believes what they tell her, she finds out too late to turn back... and that's why I tell you that young man is wasting his time."

"I believe just the contrary, as you yourself say that sometimes the girl has faith, in spite of everything."

"Well, you see I have profited by another's experience. For I have a friend... oh, the unhappy girl! When I think of the tears she has shed, and the way her father abused her!... and then the esteem she has lost through one of those rascals who deceived her! No, no, poor I was born and poor I'll remain. I don't care, for one, to be made a lady at that price!"

"And quite right you are about it. But with all this you don't dismiss your adorer, I notice."

"Oh, there's no danger so far, and there never will be;... not if I know myself, and I think I do."

"Yes, I think you do!"

"You see, we've agreed not to take any notice of these swells,... but the time for the dances comes round, and as you know, they all go to the dances. For that's a queer thing about our balls... all the men who go to the ladies' balls come to ours too, and a good many more beside. Then you see they dance with us, say such pretty things, and then... what can a girl do? Of course..."

"And all this amounts to saying that the young man yonder will not quite waste his time."

"It seems to me you are in the same boat!"

"Oh, Theresa! Would that I could be! Though it would be hard to go shares..."

"Why so?"

"Because you are so very pretty!"

"Ah, now you're going to flirt with me?"

"Yes, if you will play back!"

"And what if I tell the red-head?"

"I don't care to know her, except by sight."

"Anyway, I don't care for you."

"Thank you for your fine frankness!"

"You have a bad opinion of women."

"If they all treated me as you do, I should have a fair excuse!"

"Now you've made me break a needle."

"Never mind, I'll give you a whole package."

"At this rate I shan't get this shirt done in a week."

"So much the better. I shall see you all the oftener."

"And the work will cost you a pretty penny."

"At this price you may keep on making me shirts forever!"

"If you don't haggle about the time, then, I'm going to rob you to-day of a quarter of an hour."

"To chat with me? even if you took half a day..."

"No, no, just to go to a shop near High Street, to buy... a penny's worth of dried fruits, which I adore."

"Come, come, none of your tricks, Theresa!"

"As she gets them from Castille by wholesale, the shop woman, a friend of mine, gives me many more for a penny than they do in other shops. Don't you like them yourself?"

"No!"

"My! how queer! Will you please hand me that bit of tape down there near you, to tie up my work with?... Thank you... but how bad your face does look, all of a sudden!"

"Well, you see I have... a swelling on my gum..."

"And didn't it hurt you before?"

"Not so much as it does now, no."

"Then you'd better try a dried fig... they're awfully good for swellings."

"Thanks, so much!"

"And now good-bye. I'm off to buy my dried fruit."

"Good-bye, and good luck to you!"

To write a volume about the habits and customs of these mountain people without dedicating some pages to the seamstress, would be depriving Santander of one of its chief features. So important and conspicuous is this part of the population that the weaker sex there, after making some necessary exceptions, might be divided in equal parts between women who are seamstresses and those who are not. But to write of the habits of the former would be a great exposure for a person like myself who does not know them well. To be mistaken in the slightest detail would cost him dear! In short, gentle reader, I have a certain healthy respect for this seamstress class, and would hardly like to run the risk of painting her portrait.

And granting that "the style is the man," and therefore the woman too, study well this dialogue, which is true to life. See what you can make out of it, and govern yourself accordingly afterward, if Theresa considers herself injured by your deductions; in this case I assure you she would be guilty of injustice. For my own part, I am protected from her wrath by being able to say,—if I am hard put to it,—"You yourself have said it." Tu es auctor.

1 To understand to the full the subtle repartee that follows, it should be explained at this point that the word orejones may mean either a box of dried fruits or a box on the ear.

La costurera

title: The Seamstress


text:
User talk:Toohool

Please add some detail on the source of the transcript for the page you created. cygnis insignis 20:30, 22 January 2011 (UTC)
 * The title is helpful, but I only see a snippet view. Are you able to provide a link to the actual page? cygnis insignis 20:36, 22 January 2011 (UTC)
 * If you scroll down on that page, you'll find the full table of contents with links to the pages, but I've gone ahead and linked to the specific page. Toohool (talk) 20:42, 22 January 2011 (UTC)
 * Didn't work for me, the note at right says "No preview available". cygnis insignis 20:53, 22 January 2011 (UTC)
 * Maybe it's not available outside of the US. I've replaced it with an archive.org link. Toohool (talk) 20:58, 22 January 2011 (UTC)

When scans are available
Gday. When scans are available for works, we then do have a preference to use those scans for our proofreading and validation. More detail at Help:Proofread and supplemented by Help:DjVu files. When a text only version is uploaded, they become really difficult to double-check. — billinghurst  sDrewth  04:01, 27 January 2011 (UTC)

Terminating paragraphs on pages and nop
When a paragraph terminates at the end of a page, we would normally apply nop, as this will force a paragraph mark when it is transcluded, otherwise it will run the succeeding paragraph onto the end as one. — billinghurst  sDrewth  13:21, 4 February 2011 (UTC)

CCE
Index:Catalog of Copyright Entries 1950 Motion Pictures And Filmstrips Jan-Dec 3D Ser Vol 4 Pts 12-13.djvu

Want to work your formatting magic on this as well? ShakespeareFan00 (talk) 10:07, 18 May 2020 (UTC)
 * Assuming you mean splitting the pages up into columns.. It looks like it would actually require some substantial changes to the script I'm using. There are vertical rules between the columns that would require some adjustment to the algorithm for detecting where the columns are. I also currently have to manually enter the top and bottom margins individually for each page, which I would have to figure out how to automate if I want to process a whole 150-page volume (versus just processing the 5-10 pages of renewals). Right now I'm focused on getting through the artwork renewals up to 1977, but maybe by the end of that I'll have improved the script so it can work in more situations. (Or, if you're a coder, I could give you the script if you want to take a crack at it.) Thanks for your work on the artwork renewal pages, by the way. Toohool (talk) 04:12, 20 May 2020 (UTC)

 * I wasn't talking about extracting columns from the scans. I meant formatting in terms of the content I'd already cleaned up. Multi column was something I'd ignored in transcribing as you had with the Renewals initally.:) ShakespeareFan00 (talk) 07:47, 20 May 2020 (UTC)
 * Ah I see. I'm pretty focused on working on the artwork renewals from 1965 to 1977 though, since this will fill in a gap in the existing transcriptions and make the whole process of clearing images for non-renewal a bit simpler. Toohool (talk) 06:05, 21 May 2020 (UTC)

 * Yes, don't forget to consider part 11B (the prints and labels) at some point as well, next project after the artwork renewals? ;) ShakespeareFan00 (talk) 08:08, 21 May 2020 (UTC)
 * Yep, I have my eye on those too. Toohool (talk) 08:21, 22 May 2020 (UTC)

CCE
I thought you would want to know about:- c:Category:Catalogs of Copyright Entries

As they are volumes on Commons, it wouldn't be infeasible to set up Index pages for them here at Wikisource. Something to consider once you finish up the Art Renewals. It may with the support of the existing PG transcriptions being match, split against relevant PDF, to have a fully searchable version of the pre 1978 records, in the very very long term! ShakespeareFan00 (talk) 09:17, 27 June 2020 (UTC)
 * Yes, I came across those not too long ago. That would be nice, but I think you need a few more "very"s... by the time it's done, all those registered copyrights might have expired. :) Toohool (talk) 01:20, 28 June 2020 (UTC)

Newspaper.com
Hello. I would like to thank you for the note about Newspaper.com, I have applied for the access too and it has just been approved. Now I am waiting for the access details :-) Thanks very much, that was a great idea. --Jan Kameníček (talk) 08:24, 29 June 2020 (UTC)
 * Glad to help. It's really an amazing resource. Toohool (talk) 16:30, 29 June 2020 (UTC)

Excellent addition to Wikisource
Hi Toohool, many thanks for adding My Country 'Tis of Thee (editorial). Even as an Oregonian who's taken some interest in the Pulitzer prizes won in this state, I had not been aware of this. It's a resonant piece in these challenging times, I enjoyed it. (And I tweeted it.) Thank you.

I've added a number of works from the Oregonian and other newspapers, and I have been taught to title them as Oregonian/ /. Any reason not to do so here? -Pete (talk) 15:49, 20 July 2020 (UTC)
 * Glad you liked it.. I thought it was striking how relevant it is to today's times.
 * To me, that degree of hierarchy seems like overkill, given the very small number of dates that would have even 1 subpage, much less multiple subpages. But I won't object if you want to move it for the sake of consistency. (A look at PrefixIndex shows there already some inconsistencies though.) Toohool (talk) 07:04, 22 July 2020 (UTC)
 * I tend to agree with you, for that reason I have generally not used the full / / format, though I have seen others using that. I have instead used just / or even just . (This topic might be worth a discussion at the Scriptorium.) But I think these distinctions are the less important ones; my main point is, I think it should be a subpage of Oregonian and some (precise or imprecise) indication of the date, rather than just the bare title. That way, the header properly links it to other Oregonian content. -Pete (talk) 20:53, 22 July 2020 (UTC)
 * Fair enough, I've moved the page. Toohool (talk) 05:16, 23 July 2020 (UTC)

Post-publishing corrections
Hi Toohool,

Regarding this edit. It is entirely possible that this was a correction deliberately made by the Copyright Office staff, but we can't know that and in any case we do not reproduce matter that's not present in an edition as published. To do so is in violation of our annotation policy.

If you would like to make the case that this is an acceptable special case for which an exception is merited, that is something you would need to put to the community at the Scriptorium. --Xover (talk) 07:30, 8 September 2020 (UTC)

title: User talk:Toohool


text: Talk:The Seamstress

title: Talk:The Seamstress


text:
The Encyclopedia Americana (1920)/Kneeland, Abner

KNEELAND, nē'lănd, Abner, American theologian and deist: b. Gardner, Mass., 6 April 1774; d. Farmington, Iowa, 27 Aug. 1884. He was at first Baptist then entered the Universalist ministry, but later became deist. He edited Universalist literature at Philadelphia and New York, then went to Boston where he founded (1831) the Investigator. His expressed tenets brought him into the Boston Supreme Court (1836) where he was given a short sentence of imprisonment as guilty of blasphemy. He wrote ‘The New Testament in Greek and English’ (Philadelphia 1822); ‘Lectures on the Doctrine of Universal Salvation’ (1824); ‘A Review of the Evidences of Christianity’ (New York 1829). Consult Kneeland, A., ‘Review of the Trial, Conviction and Final Imprisonment. . . of A. Kneeland’ (Boston 1838); Parker, S. D., ‘Report of the Arguments of the Attorney. . . at the Trial of A. Kneeland’ (ib., 1834); ‘Review of the Prosecution against A. Kneeland’ (in Cosmopolite, ib. 1853),


text:
Author:Charles Everitt

Contributions to 1911 Encyclopædia Britannica

 * (History)
 * (Industrial)
 * (in part)
 * (History)
 * (Introduction and History)
 * (Chemistry of the Opium Alkaloids)
 * (in part)
 * (in part)
 * (Introduction and History)
 * (Chemistry of the Opium Alkaloids)
 * (in part)
 * (in part)

title: Author:Charles Everitt


text:
Author:José María de Pereda

Novels

 * Sotileza

Short stories

 * At the Fire-Light Reception
 * A Christmas Eve in Spain
 * The Last of His Race
 * The Seamstress
 * To the Indies

Excerpts

 * The Candidate Visits His Voters, from Los hombres de pro
 * Cleto's Proposal to Sotileza, from Sotileza
 * The Portrait of Don Gonzalo Gonzalez of Gonzalez-Town, from Don Gonzalo González de la Gonzalera
 * Tuerto's Family Life, from La leva

title: Author:José María de Pereda


text:
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 those operations which were almost wholly mechanical, had developed a considerable body of dental artisans who, though without medical education in many cases, possessed a high degree of manipulative skill. Thus there came to be two classes of practitioners, the first regarding dentistry as a specialty of medicine, the latter as a distinct and separate calling.

In America representatives of both classes of dentists began to arrive from England and France about the time of the Revolution. Among these were John Wooffendale (1766), a student of Robert Berdmore of Liverpool, surgeon-dentist to George III.; James Gardette (1778), a French physician and surgeon; and Joseph Lemaire (1781), a French dentist who went out with the army of Count Rochambeau. During the winter of 1781–1782, while the Continental army was in winter quarters at Providence, Rhode Island, Lemaire found time and opportunity to practise his calling, and also to instruct one or two persons, notably Josiah Flagg, probably the first American dentist. Dental practice was thus established upon American soil, where it has produced such fertile results.

Until well into the 19th century apprenticeship afforded the only means of acquiring a knowledge of dentistry. The profits derived from the apprenticeship system fostered secrecy and quackery among many of the early practitioners; but the more liberal minded and better educated of the craft developed an increasing opposition to these narrow methods. In 1837 a local association of dentists was formed in New York, and in 1840 a national association, The American Society of Dental Surgeons, the object of which was “to advance the science by free communication and interchange of sentiments.” The first dental periodical in the world, The American Journal of Dental Science, was issued in June 1839, and in November 1840 was established the Baltimore College of Dental Surgery, the first college in the world for the systematic education of dentists. Thus the year 1839–1840 marks the birth of the three factors essential to professional growth in dentistry. All this, combined with the refusal of the medical schools to furnish the desired facilities for dental instruction, placed dentistry for the time being upon a footing entirely separate from general medicine. Since then the curriculum of study preparatory to dental practice has been systematically increased both as to its content and length, until in all fundamental principles it is practically equal to that required for the training of medical specialists, and in addition includes the technical subjects peculiar to dentistry. In England, and to some extent upon the continent, the old apprenticeship system is retained as an adjunct to the college course, but it is rapidly dying out, as it has already done in America. Owing to the regulation by law of the educational requirements, the increase of institutions devoted to the professional training of dentists has been rapid in all civilized countries, and during the past twenty years especially so in the United States. Great Britain possesses upwards of twelve institutions for dental instruction, France two, Germany and Switzerland six, all being based upon the conception that dentistry is a department of general medicine. In the United States there were in 1878 twelve dental schools, with about 700 students; in 1907 there were fifty-seven schools, with 6919 students. Of these fifty-seven schools, thirty-seven are departments of universities or of medical institutions, and there is a growing tendency to regard dentistry from its educational aspect as a special department of the general medical and surgical practice.

Recent studies have shown that besides being an important part of the digestive system, the mouth sustains intimate relationship with the general nervous system, and is important as the portal of entrance for the majority of the bacteria that cause specific diseases. This fact has rendered more intimate the relations between dentistry and the general practice of medicine, and has given a powerful impetus to scientific studies in dentistry. Through the researches of Sir J. Tomes, Mummery, Hopewell Smith, Williams and others in England, O. Hertwig, Weil and Röse in Germany, Andrews, Sudduth and Black in America, the minute anatomy and embryology of the dental tissues have been worked out with great fulness and precision. In particular, it has been demonstrated that certain general systemic diseases have a distinct oral expression. Through their extensive nervous connexions with the largest of the cranial nerves and with the sympathetic nervous system, the teeth frequently cause irritation resulting in profound reflex nervous phenomena, which are curable only by removal of the local tooth disorder. Gout, lithaemia, scurvy, rickets, lead and mercurial poisoning, and certain forms of chronic nephritis, produce dental and oral lesions which are either pathognomonic or strongly indicative of their several constitutional causes, and are thus of great importance in diagnosis. The most important dental research of modern times is that which was carried out by Professor W. D. Miller of Berlin (1884) upon the cause of caries of the teeth, a disease said to affect the human race more extensively than any other. Miller demonstrated that, as previous observers had suspected, caries is of bacterial origin, and that acids play an important rôle in the process. The disease is brought about by a group of bacteria which develop in the mouth, growing naturally upon the débris of starchy or carbohydrate food, producing fermentation of the mass, with lactic acid as the end product. The lactic acid dissolves the mineral constituent of the tooth structure, calcium phosphate, leaving the organic matrix of the tooth exposed. Another class of germs, the peptonising and putrefactive bacteria, then convert the organic matter into liquid or gaseous end products. The accuracy of the conclusions obtained from his analytic research was synthetically proved, after the manner of Koch, by producing the disease artificially. Caries of the teeth has been shown to bear highly important relation to more remote or systemic diseases. Exposure and death of the dental pulp furnishes an avenue of entrance for disease-producing bacteria, by which invasion of the deeper tissues may readily take place, causing necrosis, tuberculosis, actinomycosis, phlegmon and other destructive inflammations, certain of which, affecting the various sinuses of the head, have been found to cause meningitis, chronic empyema, metastatic abscesses in remote parts of the body, paralysis, epilepsy and insanity.

Operative Dentistry.—The art of dentistry is usually divided arbitrarily into operative dentistry, the purpose of which is to preserve as far as possible the teeth and associated tissues, and prosthetic dentistry, the purpose of which is to supply the loss of teeth by artificial substitutes. The filling of carious cavities was probably first performed with lead, suggested apparently by an operation recorded by Celsus (100 ), who recommended that frail or decayed teeth be stuffed with lead previous to extraction, in order that they might not break under the forceps. The use of lead as a filling was sufficiently prevalent in France during the 17th century to bring into use the word plombage, which is still occasionally applied in that country to the operation of filling. Gold as a filling material came into general use about the beginning of the 19th century. The earlier preparations of gold were so impure as to be virtually without cohesion, so that they were of use only in cavities which had sound walls for its retention. In the form of rolls or tape it was forced into the previously cleaned and prepared cavity, condensed with instruments under heavy hand pressure, smoothed with files, and finally burnished. Tin foil was also used to a limited extent and by the same method. Improvements in the refining of gold for dental use brought the product to a fair degree of purity, and, about 1855, led to the invention by Dr Robert Arthur of Baltimore of a method by which it could be welded firmly within the cavity. The cohesive properties of the foil were developed by passing it through an alcohol flame, which dispelled its surface contaminations. The gold was then welded piece by piece into a homogeneous mass by plugging instruments with serrated points. In this process of cold-welding, the mallet, hitherto in only limited use, was found more efficient than hand pressure, and was rapidly developed. The primitive mallet of wood, ivory, lead or steel, was supplanted by a mallet in which

title: Page:EB1911 - Volume 08.djvu/66


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Page:EB1911 - Volume 08.djvu/67

 a hammer was released automatically by a spring condensed by pressure of the operator’s hand. Then followed mallets operated by pneumatic pressure, by the dental engine, and finally by the electro-magnet, as utilized in 1867 by Bonwill. These devices greatly facilitated the operation, and made possible a partial or entire restoration of the tooth-crown in conformity with anatomical lines.

The dental engine in its several forms is the outgrowth of the simple drill worked by the hand of the operator. It is used in removing decayed structure and for shaping the cavity for inserting the filling. From time to time its usefulness has been extended, so that it is now used for finishing fillings and polishing them, for polishing the teeth, removing deposits from them and changing their shapes. Its latest development, the dento-surgical engine, is of heavier construction and is adapted to operations upon all of the bones, a recent addition to its equipment being the spiral osteotome of Cryer, by which, with a minimum shock to the patient, fenestrae of any size or shape in the brain-case may be made, from a simple trepanning operation to the more extensive openings required in intra-cranial operations. The rotary power may be supplied by the foot of the operator, or by hydraulic or electric motors. The rubber dam invented by S. C. Barnum of New York (1864) provided a means for protecting the field of operations from the oral fluids, and extended the scope of operations even to the entire restoration of tooth-crowns with cohesive gold foil. Its value has been found to be even greater than was at first anticipated. In all operations involving the exposed dental pulp or the pulp-chamber and root-canals, it is the only efficient method of mechanically protecting the field of operation from invasion by disease-producing bacteria.

The difficulty and annoyance attending the insertion of gold, its high thermal conductivity, and its objectionable colour have led to an increasing use of amalgam, guttapercha, and cements of zinc oxide mixed with zinc chloride or phosphoric acid. Recently much attention has been devoted to restorations with porcelain. A piece of platinum foil of .001 inch thickness is burnished and pressed into the cavity, so that a matrix is produced exactly fitting the cavity. Into this matrix is placed a mixture of powdered porcelain and water or alcohol, of the colour to match the tooth. The mass is carefully dried and then fused until homogeneous. Shrinkage is counteracted by additions of porcelain powder, which are repeatedly fused until the whole exactly fills the matrix. After cooling, the matrix is stripped away and the porcelain is cemented into the cavity. When the cement has hardened, the surface of the porcelain is ground and polished to proper contour. If successfully made, porcelain fillings are scarcely noticeable. Their durability remains to be tested.

Until recent times the exposure of the dental pulp inevitably led to its death and disintegration, and, by invasion of bacteria via the pulp canal, set up an inflammatory process which eventually caused the loss of the entire tooth. A rational system of therapeutics, in conjunction with proper antiseptic measures, has made possible both the conservative treatment of the dental pulp when exposed, and the successful treatment of pulp-canals when the pulp has been devitalized either by design or disease. The conservation of the exposed pulp is affected by the operation of capping. In capping a pulp, irritation is allayed by antiseptic and sedative treatment, and a metallic cap, lined with a non-irritant sedative paste, is applied under aseptic conditions immediately over the point of pulp exposure. A filling of cement is superimposed, and this, after it has hardened, is covered with a metallic or other suitable filling. The utility of arsenious acid for devitalizing the dental pulp was discovered by J. R. Spooner of Montreal, and first published in 1836 by his brother Shearjashub in his Guide to Sound Teeth. The painful action of arsenic upon the pulp was avoided by the addition of various sedative drugs,—morphia, atropia, iodoform, &c.,—and its use soon became universal. Of late years it is being gradually supplanted by immediate surgical extirpation under the benumbing effect of cocaine salts. By the use of cocaine also the pain incident to excavating and shaping of cavities in tooth structure may be controlled, especially when the cocaine is driven into the dentine by means of an electric current. To fill the pulp-chamber and canals of teeth after loss of the pulp, all organic remains of pulp tissue should be removed by sterilization, and then, in order to prevent the entrance of bacteria, and consequent infection, the canals should be perfectly filled. Upon the exclusion of infection depends the future integrity and comfort of the tooth. Numberless methods have been invented for the operation. Pulpless teeth are thus preserved through long periods of usefulness, and even those remains of teeth in which the crowns have been lost are rendered comfortable and useful as supports for artificial crowns, and as abutments for assemblages of crowns, known as bridge-work.

The discoloration of the pulpless tooth through putrefactive changes in its organic matter were first overcome by bleaching it with chlorine. Small quantities of calcium hypochlorite are packed into the pulp-chamber and moistened with dilute acetic acid; the decomposition of the calcium salt liberates chlorine in situ, which restores the tooth to normal colour in a short time. The cavity is afterwards washed out, carefully dried, lined with a light-coloured cement and filled. More efficient bleaching agents of recent introduction are hydrogen dioxide in a 25% solution or a saturated solution of sodium peroxide; they are less irritating and much more convenient in application. Unlike chlorine, these do not form soluble metallic salts which may subsequently discolour the tooth. Hydrogen dioxide may be carried into the tooth structure by the electric current. In which case a current of not less than forty volts controlled by a suitable graduated resistance is applied with the patient in circuit, the anode being a platinum-pointed electrode in contact with the dioxide solution in the tooth cavity, and the cathode a sponge or plate electrode in contact with the hand or arm of the patient. The current is gradually turned on until two or three milliamperes are indicated by a suitable ammeter. The operation requires usually twenty to thirty minutes.

Malposed teeth are not only unsightly but prone to disease, and may be the cause of disease in other teeth, or of the associated tissues. The impairment of function which their abnormal position causes has been found to be the primary cause of disturbances of the general bodily health; for example, enlarged tonsils, chronic pharyngitis and nasal catarrh, indigestion and malnutrition. By the use of springs, screws, vulcanized caoutchouc bands, elastic ligatures, &c., as the case may require, practically all forms of dental irregularity may be corrected, even such protrusions and retrusions of the front teeth as cause great disfigurement of the facial contour.

The extraction of teeth, an operation which until quite recent times was one of the crudest procedures in minor surgery, has been reduced to exactitude by improved instruments, designed with reference to the anatomical relations of the teeth and their alveoli, and therefore adapted to the several classes of teeth. The operation has been rendered painless by the use of anaesthetics. The anaesthetic generally employed is nitrous oxide, or laughing-gas, the use of which was discovered in 1844 by Horace Wells, a dentist of Hartford, Conn., U.S.A. Chloroform and ether, as well as other general anaesthetics, have been employed in extensive operations because of their more prolonged effect; but chloroform, especially, is dangerous, owing to its effect upon the heart, which in many instances has suddenly failed during the operation. Ether, while less manageable than nitrous oxide, has been found to be practically devoid of danger. The local injection of solutions of cocaine and allied anaesthetics into the gum-tissue is extensively practised; but is attended with danger, from the toxic effects of an overdose upon the heart, and the local poisonous effect upon the tissues, which lead in numerous cases to necrosis and extensive sloughing.

Dental Prosthesis.—The fastening of natural teeth or carved substitutes to adjoining sound teeth by means of thread or wire preceded their attachment to base-plates of carved wood, bone or ivory, which latter method was practised until the introduction of swaged metallic plates. Where the crown only of a tooth or those of several teeth were lost, the

title: Page:EB1911 - Volume 08.djvu/67