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Rh Draw the line from L to K in the trne perpendicular; from G which is at the front of scye to H, from I to J, from K to M, and from I to N, and

The same variation in the length of the waist to be made as was done with the back. For a sleeve, draw a line as from A through B to 0, and vary ½ an inch for every 2 inches in the total breast; vary the width at the elbow about ⅜ and at the cuff ¼ inch for every 2 in. total breast, whilst the length may be shortened say ½ an inch for the small ones at the cuff in addition to the variation in the length produced by the grading at the top, which latter will be found quite sufficient for the large sizes. The collar only requires varying ⅜ at the back at X, Diagram 123, the front at N N being left the same, a trifle narrower at W being perhaps needed for the small sizes. This then constitutes the method of grading, and where it is desirable to reproduce a given style of pattern with special characteristics, it will be found a very effective method, and is specially suitable for manufacturing trades rather than the artist tailor who caters for the wants of every customer on separate lines, so as to obtain the highest results, rather than to produce a set of patterns with the same characteristic running throughout the whole set.

There are, of course, many other features and details associated with ladies' tailoring, but which the scope of this work, large as it is, will not permit of being treated here. These will be found, from time to time, in our monthly journal, the Ladies' Tailor'.

Before concluding, we feel it imperative to lay a few claims for art before oar readers, as the subject is of such vast importance. There is so much that might be written upon it, that the difficulty presents itself, in deciding what to leave out. and what to give; but after a little consideration, we think this will be met so far by a brief treatment of the subject under the three headings of

Form, Colour, and Ornamentation, Which may suffice to awaken an interest in our readers' minds, and so induce them to study it more deeply from those works specially devoted to it. Form and colour have been called the vowels and consonants of the silent language of creation. It is by their aid that nature discloses all that is beautiful, lovely, or sublime. Sometimes she employs them separately, sometimes together, but however used, there is always one more dominant than the other, the secondary element merely adding beauty to the primary, and in this way forms ornamentation, and consequently ornamentation may consist of either form or colour, or both, We will take each of these features in turn, and make a brief survey of it in its various phases from a tailor's standpoint. Let us take first

First of all there is the form of fit, embracing not only the shape in which the garment is cut, but also the form that is infused by the tailor's manipulation—stretching, shrinking, building up, or toning down, in all its various phases; all of which go to make up a garment of beauty. Then there is the form of style, the fashion phase of the subject, and this involves a study, not only the styles of the period, but also the habits of life, the social position, the age, and the form of the body in order to arrive at a suitable style of out-line for the garment. Let us take a brief glance at

A study of our earlier pages, where we treat of anatomy somewhat fully, will show the cutter where the prominence and depressions of the body are to be found, and if he is in any doubt, let him study his own body, and he will soon realise the importance of making provision for these; this may either be done by cut or manipulation. Of the matter of cut we have treated in our section dealing with "The Principles of Fit: " and


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54 as long as the seams runs exactly over the prominence or depression, all that is necessary will he to provide for them by suppressions, &c.; but as soon as the seams run to the one side or the other, then manipulation will be necessary, as for instance in the sideseams: if the back is cut very wide and straight, then the back must be fulled on to the sidebody; but if narrow and hollow, then the sidebody must be fulled on, so that the pocket, as it were, for the prominence, is located in the right place. But if the cutter once realises that the human figure has its points of depression and prominence, and that the garment he is cutting has to fit that, and not to lie flat and smooth on a board, then he will realise the importance of the form of fit.

May then claim his attention. Fashion must be consulted, but if he would be an artist tailor he must tone down fashion follies by the application of art rules. If the' garment is loose and baggy, vertical lines may be introduced to take away the shortening tendency of the amplitude of width. This may be either done by the use of striped material, the position of the seams or the method of ornamentation. The multiplication of seams makes the various parts narrower, and so introduces length, and our readers will And ladies are quite aware of this phase of the subject, and will expect the cutter by this means to modify or tone down any defect that may exist in their figure. Always avoid sharp angles; let your lines run with graceful sweeps; there are scarcely any sharp angles in the outline of the human figure, all are softened down, and instead of a sharp angle there is a graceful curve: and if we remember the aims of art are to elevate, to enable, to beautify, we shall realize that in nature we have our copy, and that it should be our aim to present nature in its most ideal forms; and this it will he found can only be done by the avoidance of angles and the introduction of curves. Study Hogarth's line of beauty, infuse it in the outline of your garments, and you will soon be a master of art of improving the form of style. It will at once be apparent that it would be out of keeping to dress an elderly person up as a young one, or a peasant as a king, so we will leave this phase of the subject, and hasten on to a study of that all important one

Under this heading we must take a brief glance at (1) the combination of various shades or hues, so that each shall assist the other; (2) the effects and suitability of the various colours for different complexions: and (3) the artistic effect of checks and stripes. Colour depends on light. In the dark all colours are the same and we know the single ray of white light is composed of all colours, and is easily divisable by the prism into red, orange, yellow, green, blue, violet, and indigo. These seven were looked upon by Sir Isaac Newton as primary colours, or colours of the first importance: but specialists in this branch, such as Sir David Brewster, now look upon red, yellow, and blue as the only primaries, contending that the others are produced by the mixture of these in some form or other, and that these three stand out as the elements of colour. White and black are not colours themselves, but represent light and darkness, whilst a mixture of the two forms the neutral tint we call grey. Every colour has its complementary, this is composed of the remaining portions of the three primaries not used in its formation; thus the complementary of red is green; of yellow, purple: of blue, orange. The green, purple, and orange being the mixture of the other two primaries required to make white light. To produce harmony in colour or complete satisfaction to the eye, the presence of all three primaries is required, either alone or a combination: and when so used they each add to the intensity of the other; thus red appears much redder when placed on green, and so on. But it is not necessary to combine them just in those forms, half shades or tertiary colours produce a less glaring effect: they are produced by a mixture of the three primaries in different quantities. Citrine, russet, and olive are the three most important tertiaries. In citrine there is a predominance of yellow, hence it harmonises well with purple or violet. In olive there is an extra quantity of blue, it harmonises well with orange; and russet, which is largely composed of red, harmonises well with green, or proper proportions of olive and citrine. The complementary arrangement as above described, says "Chevruel," is of the first importance. In Diagram 127 the complementary colours are arranged opposite each other, thus blue and orange, red and green, and so on: the triangle shows the three primaries, whilst between each point is illustrated the combination of the primaries to produce binaries: thus equal portions of yellow and blue produces green; a preponderance of yellow gives a yellowish green, and so on. Combinations of the same colour on different shades is called the harmony of analogy, and often produces some very pretty effects, as in the combination of Oxford and Cambridge blues; but when two tones of the same colour are placed side by side in this way, the dark one will appear darker, and the light one lighter. When locking at a bright colour on a black ground, there is a tendency for the eye to surround it with its complementary, and thus often make the black suffer. Bet us now examine the suitability of the different

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Rh For our purpose we will divide the complexions into two classes, the dark and the fair, or the brunette and the blonde. As a general rule it will be found reds and yellows suit dark people best, and blue is the colour which shows off the fair beauty to the best advantage. Black, white, and grey suit all people; a soft deep black, such as velvet, will set off a blonde; whilst a bright black, such as black satin, will set off the brunette. White, and all those colours which reflect the most light, have the effect of making people appear larger than they are; whilst black, and all colours which absorb the light, make people look smaller, and consequently a stout person would appear to best advantage in a black dress of dull material: whilst, on the other hand, a little woman would be seen to the best advantage in a white dress made from some brilliant material. Before quitting this subject we must not omit to point out

And details of a costume: such, for instance, as head gear, gloves, parasol, shoes, &c., which must not only be in harmony with the costume, but combine with it the complexion, the colour of hair, eyes, &c., to form the complement of colour. Many a firm has made a lasting reputation by attention to such details: and if we would follow in their footsteps, we must attach due importance to these matters, and study them accordingly.

Colour helps to give expression to form, and probably the pattern of material is the best illustration we can give of this: and as different styles of patterns have different effects, independent of the colours embraced in their formation, it will be well for us to examine this phase.

Stripes add length in whatever direction they are running, they are nearly always popular running vertically, as in Diagram 128, as in that way they add height to the figure: they are seldom used horizontally or running round the figure, as Diagram 129, as in such a manner they make the figure wider and shorter (a reference to diagrams will illustrate this, the circles having the appearance of being slightly oval by elongating effect of the stripes). They are sometimes worn on the bias, but they are then apt to give the figure a one-sided appearance, a twisting corkscrew effect being produced. They are especially suitable for short stout people when arranged vertically, though in extreme cases it is always best to avoid very prominent patterns: stripe in such a case should be dark and neat.

Checks add width to the figure, without increasing the height: they also show up the slightest difference in the sides, by cutting the figure up in squares. Prominently checked goods are only suitable for very fine types of figure, though small and neat checks may be used by the ordinary run of people without disadvantage, as owing to the distance from the onlookers eye, the effect of the neat check would be the same as a self pattern. In all cases of doubt, select quiet neat patterns and on toned colours. A plain twill or bird's-eye check suits well nigh everyone, as also does black, white, and grey. This brief glance at colour must suffice for this work, those who are desirous of studying it more deeply may get works especially devoted to its explanation. We now pass on to deal with

The five principles of ornamentation are as follows: repetition, alternation, symmetry, progression and confusion, and it is to one or other of these primary sources that all ornamentation may he traced, and in order to fully illustrate, we give diagrams of the various modes as applied to braiding designs, considering that the most suitable for the purpose, though any other style of trimming may be subjected to the same laws. Let us briefly glance at

This is the simplest method of decoration, hut at the same time it is one of the best. It is the method nature uses more than any other. Every thing that appeals to our senses acquires an astonishing power by repetition, and so with the style of braiding illustrated. A single eye of braid would be hardly noticable, but the repetition adds force, and shows at once the design has all the elements of beauty, viz., unity, order and proportion. Architecture, sculpture, painting, music, literature and poetry, are all embellished by repetition, indeed, there is no principle which appears more frequently either in the works of man or the works of nature. Consonance is the secondary element of repetition, by it we mean the repetition of idea rather than the actual reproduction. Take for instance the flaps on a Reefer or Lounge: they are made in consonance with the front, that is, if the front is rounded away, the flap is done ditto, and so on: this will explain what we mean by consonance.

Variety is one of the great laws of the universe, and alternation is a blending of variety and repetition This will be gathered from a reference to diagram


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56 where the braiding alternates, first forming a crow's toe and then a simple eye. It is the succession of two different objects or forms recurring regularly in turn. There can be no alternation without repetition, but there can be repetition without alternation. Day and night are admirable illustrations of this principle. Contrast is the highest degree of alternation, it gives character and go to the part it is applied to, and if used aright, strengthens the unity of the subject, by emphasizing its various parts, and bringing much within range that would otherwise have been lost sight of.

The human body is symmetrical. When we stand face to face with a human being, his body appears to be composed of two halves united in the centre, and these two parts, without being identical, correspond in such a manner that the right side, if folded over on the left, would exactly cover it. This repetition in reverse is what is called symmetry, though the original meaning of the word signified what we now understand by proportion. Diagram 132 is a capital illustration of symmetrical braiding, and is a copy of a military design for a cuff. Radiation is a form of symmetry in which all its parts are alike; that is, suppose a complete circle was formed of designs as illustrated on diagram 133, it could be folded over any way, and would come exactly on the top of a similar design. Doubtless our readers will remember how popular this method of trimming ladies' bodices round the scye was a very short time since.

Perspective is a highly attractive example of progression. Progression is a gradual leading up to a point where a climax is reached, which appears far more beautiful than it would without the preparation of progression. Diagram 134 is an example of progression, and so is diagram 132, the ornament at the base gradually increase till the knot is reached. Progression and gradation are not quite the same. Progression may be irregular, gradation is never so. The numbers 1, 3, 5 7, 9, illustrate progression, but they have no resemblance to 2, 4, 8, 16, 32, the latter is a regular succession of changes, the former a series of shades.

These are not so often used in tailoring, still we do occasionally see garments braided without any apparent design—a sort of higgledy-piggledy arrangement, but in the midst of this disorder, these must be order introduced, if it is to become ornament: thus the outline of the braiding must be clearly defined, either by a border limiting its outline. In nature we frequently find a fine disorder which produces a beautiful effect, but the charm which nature throws over her works by careless foliage of trees, the dasies in the field, the stars in the heavens, cannot be reproduced in costume. Nature's fields are so wide that we can only take in a portion at one view. Doubtless if we could take in the whole of the universe, it is quite possible we should find some features of balance introducing order in the same way that we do in the minor works of nature.

Much more might be written on this subject, but this must suffice. We have briefly touched on the principal features, and if we have not gone into these matters as fully as some of our readers would desire, we must plead the impossibility of treating every phase of this vast subject of ladies' tailoring within the limits of one volume.

Ere we lay aside our pen, we will only state by way of conclusion, that we have aimed at the production of a work that should supply the young cutter with all he may require to fit him for the post of a ladies' tailor. Such has been our aim, our readers will judge whether we have succeeded in carrying out that aim to a practical issue. We desire to instruct, to improve, to encourage, and it may be that even in the defects of our work, others may take courage and persevere midst adverse circumstances and innumerable difficulties till a successful issue results. It is in this frame of mind, acknowledging its defects, regretting its imperfections, that we say, as we look upon our finished work, we feel proud of it. We have done our best; neither time nor trouble has been spared: and we have little doubt that the trade will receive it and use it according to its merits, of which others will be the best judge, rather than

THE AUTHOR.


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 life, and I believe others did the same. This was only natural in such a number of young men all having the same object in view, especially when their views on religious, social, or political subjects were much in common. There were very few of them who went in for politics, but many a discussion took place on religion and temperance ; and very instructive they frequently were, too, carried on as they usually were in the best of humours whilst we were busy with our drawing books, drafting models, &c. Young men from all parts of Great Britain were there, Welshmen, Irishmen, Scotchmen, Yorkshiremen ; and not only from our own little island, but there was a Canadian, an American, a New Zealander, an Australian ; and I heard from the secretary it was no unusual occurrence for them to have 6 or 7 different nationalities represented there at the same time, Russians, Frenchmen, Germans, Swedes and Jews often forming part of the company. Sometimes they could speak English, sometimes they could not and it was astonishing how well they could be taught without the use of the tongue. This reminds me that whilst I was there, we had a deaf and dumb fellow student ; and he really got on well, for though only there for a month, yet he thoroughly mastered Coats, Vests, and Trousers, and successfully passed his examination. I soon felt at home with them all, for they were jolly fellows and

I began to feel myself an old stager, for I had seen many come and go in that time. Some cutters in actual practice would get a week's holiday, and come up to learn a little about their weak points ; with some it was breeches, with others it was ladies', and I often envied the speed with which they acquired the knowledge in their special branch they had come up to study. I had, as I have stated, come for three months, and the plan followed with long term Students, is to thoroughly ground them in each garment as they proceed, so that I had not advanced very far at this time, though there is many a man holding a cutter's position, that knows no more than I did at that time, for I had thoroughly mastered the cutting of Trousers, Breeches, Gaiters, Vests, Lounges, Morning and Frock Coats, Overcoats, dec., and had begun the study of disproportion. I knew how to provide for stooping and erect figures, long and short necks, and was dealing with hump backs, &c., when Was given on this very subject. One of the Students consented to have his body made up by padding, &c., to represent a very bad case of disproportion ; one of the teachers being deputed to do this, and the form he produced, was such that I think I should shudder to see enter my cutting room now. I will try to describe it ; There was a large hump on the right side, with a corresponding depression on the left, the right shoulder was at least 2 inches higher than the left, and though the chest was 36 yet the measure across was only $6 3⁄4$, that is $13 1⁄2$ from arm to arm. The senior teacher then commenced operations. He took the measures, cat the pattern, marked it on the cloth, cut it out, basted it up, all the while explaining every detail as he proceeded and answering the hundred and one questions asked him as he went on. Sometimes I wondered at the patience and good humour shown by the teachers, and I can only say they are indeed men well qualified for their position. The one special note I made on the subject of deformities was : " Don't try to exactly fit, but to hide the deformity." I have many others, but this was the special teaching on that occasion, and I must say the result of the try on was a great success. About this time there were several leaving, their terms of tuition having expired, and they asked to be taken over the premises, so I joined them in their

We started at the basement, and as we got to this we could see the engine puffing away, and very quickly we were amidst the noise and din of four large printing machines, all busy at work. One was printing Fashion Plates, another was printing a portion of a New Work in course of preparation, and the other two were occupied with the Tailor and Cutter and the Ladies' Tailor. In the corner of one of the large printing rooms was the guilotine, which cuts and trims the edges of the journals, &c., before they are sent out. After watching with interest the various processes in operation in the basement, we came up to the ground floor ; here the Clerk's Office is situated, together with the Secretary's Room, a stock room and the shop. Around the walls of the latter large cupboards are fitted up, these are fitted with pigeon-holes, which are fitted with the various kinds of Model Patterns supplied. In a glass case were displayed samples of Shears, Scissors, Squares, &c., and in another the various works on cutting published by the company. On the walls were hung specimens of Fashion Plates, including Military, Naval and Livery Plates ; and I could not help thinking how nicely they would show off the walls of any cutting room. We then ascended to the Cutting Rooms on the first floor, which I have already described ; by the side of this is placed the Editor's Room, which forms a centre of the establishment, and from whence instructions for each department emanate. Above this is a room I hear the company are specially fitting up for Ladies, in addition to a small room on the first floor. By the side of this is another Stock Room, where piles of Books, Plates, Trouser Stretchers, &c., were to be seen. Back we came through the Lavatory, into the upstairs Cutting Room, and then at the back of this we were shown the Model Pattern Cutting Room, where the world-famed Models are ranged round the walls, and from which copies are cut by the score. It was very interesting to see the knife at work in the hands of a skilled cutter, and what struck me. most was the accuracy and care with which every detail was attended to, in order to make these model patterns models indeed. On the third and top floor we found the compositors busy with their formes and type. There we were shown the engraved blocks of diagrams, the method by which they were produced was explained, and so on till a good quarter of an hour had been spent in a most instructive manner. To the right of the compositors room we were ushered into the folding room, where we found four young ladies, busy at work, folding the journals ; how nimbly their hands manipulated the sheets, how quickly and accurately it was all done ; truly practice makes perfect. Ere descending the stairs we were shown the lift, by which all the heavy forms of type, &c., are transported from the compositors to the printers. This brought our tour of inspection to a close, a tour that demonstrated to me how necessary co-operative effort was to produce anything of benefit to the world at large, and I think there are few indeed but will readily acknowledge the Tailor and Cutter is a benefit to the tailoring community in particular, and through them to the world generally. I now began to think of serious I was supplied with a list of questions which seemed to me to embrace every phase of tailoring— practical, scientific, and artistic. I was told to study them all, to be capable of answering every one, though I should only get a small selection from them to answer in my examination. Having got this list, I cut the sheets up so that each question was separate, and these I pasted in a twopenny exercise book, allowing some five or six lines to write my answer in. Having done this, I was ready to start. There is no key book from which to crib the answers from ; each has to be carefully studied out ; still I did not find them particularly difficult, though some of them were what I should call "tricky


text:
Author:Ismaël Bullialdus

Works

 * De natura lucis (1638)
 * Philolaus (1639)
 * Expositio rerum mathematicarum ad legendum Platonem utilium, translation of Theon of Smyrna (1644)
 * Astronomia philolaica (1645)
 * De lineis spiralibus (1657)
 * Opus novum ad arithmeticam infinitorum (1682)
 * Ad astronomos monita duo (1667)

title: Author:Ismaël Bullialdus


text:
Author:Balthasar de Monconys

Works

 * Journal des voyages de Monsieur de Monconys, Conseiller du Roy en ses Conseils d’Estat & Privé, & Lieutenant Criminel au Siège Presidial de Lyon

title: Author:Balthasar de Monconys


text:
Page:Scientific Memoirs, Vol. 1 (1837).djvu/29

Rh surface, the colour, and the internal structure of a body, as well as its chemical composition, have any influence whatever in the quantity of heat which it transmits immediately; and that, in this point of view, the origin and the qualities of the caloric rays become objects of perfect indifference; for it is enough for our purpose that the rays be invariable and identical in all the circumstances in which they are employed. Now this actually is the case with the rays issuing from the well supported flame of a Quinquet lamp placed at a fixed distance.

When we shall have found the ratios of the quantities of heat transmitted by screens of different kinds under the influence of a constant source, then, agreeably to what we have stated in the introduction, we shall examine the changes which those ratios undergo in consequence of the variation of the sources.

All our experiments of comparison have been made with the same calorific radiation. Previously to the commencement of each series the rays were allowed to fall directly on the pile, and the distance of the lamp was modified until the needle of the galvanometer fixed itself at 30° of the scale.

We have remarked in the preliminary considerations, that all the external parts of the thermoscope are sheltered from the caloric rays by means of a large screen of polished metal, having in its central part a hole to correspond with the opening of the pile turned towards the lamp.

In order to establish or to intercept the communication between this aperture and the source of heat securely and commodiously, we make use of a moveable copper screen, consisting of two or three parallel plates fixed on the same support. The side of the pile opposite to the lamp may also be closed and opened by means of a screen altogether similar, and for the following purpose:

When, after having observed the effect of any radiation whatsoever, we intercept the action of the source, we must wait until that face of the pile on which the rays of heat are darted has been restored to it natural state before we make a second observation. Now it appears that the heat emitted by the flame penetrates the apparatus with greater ease than it issues from it, because of its natural tendency to an equilibrium. At least the experiment shows that the time requisite to produce the deviation is to that in which the needle recovers its original position nearly as one to five; for the latter is from 7s to 8s and we have seen that the whole deviation is produced in a minute and a half. Whatever be the cause of this difference between the time required for heating and that required for cooling, we must always allow 8s to elapse after one experiment before we proceed to another, if we confine ourselves to the placing of the first moveable screen before the radiating source. But let the opposite side of the pile be opened and a lighted candle brought close to the corresponding face: it is evident that if the


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Page:Scientific Memoirs, Vol. 1 (1837).djvu/30

18 candle be held for some minutes at a suitable distance, and the communication then intercepted, the needle will be forced back to zero in an interval of time less than 8s. These operations would be impossible if the side of the pile opposite to the lamp were hermetically closed. The second moveable screen serves then to abridge the duration of the experiments. It is particularly useful when the calorific action has been very powerful or considerably prolonged, which sometimes happens in the first attempts at adjustment. During these, the portions of heat penetrate the pile to a great depth, and cannot return until a considerable time has elapsed. Before these simple means of correction had occurred to me, the difficulty of restoring the equilibrium of the two extremes of the pile, as well as that which I experienced in respect to he different temperatures of the screens and the apparatus, often obliged me to stand still for fifteen or twenty minutes between two consecutive experiments.

When any object of research requires numerous experiments, we should endeavour from the very outset to avail ourselves of all that contributes to make them more expeditious; for the least delay arising from imperfectness of method will, by gradually accumulating, ultimately render the labour of whole days utterly fruitless. Yet, the attention being absorbed by the main object, these little defects are at first unnoticed. At length, however, we become sensible of them, and endeavour to apply a remedy when it is almost too late. But the result of the experiment is not without its use, since it may be more or less serviceable in analogous circumstances. This consideration must be my apology for the minuteness of detail into which I have entered.

The first problem that presents itself, in the series of questions relative to the passage of radiant heat through solid bodies, is to determine the influence which the degree of their polish has, and the quantity of rays transmitted. In order to solve this, we have but to apply our thermometrical method to several screens perfectly similar in all respects, except as to the state of the surface.

Out of the glass of a mirror which was very pure, and nine millimetres in thickness, I cut eight pieces sufficiently large to cover the central aperture of the screen when they were placed on the stand; and, after having removed the quicksilver, I wore them down with sand, emery, and other such substances, so as to form by their succession a complete series of plane surfaces more or less finely wrought, from the first and coarsest to the highest and most perfect polish. These different pieces reduced to one common thickness of 8mm·371 and


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Rh to a radiation of 30° of the thermomultiplier, have furnished the following results:

These transmissions present nothing extraordinary: the quantity of heat which passes through the medium is greater in proportion as the surface is more finely polished, as it happens in respect to light. The only thing to be remarked is, that in the high degrees of polish a slight difference produces a very slight effect. This is evident from the observations made on Nos. 7 and 8.

Similar processes enable us to determine the influence of thickness, which is one of the elements most necessary to be known in the theory of transmission.

Four pieces cut out of a fine mirror were reduced with great nicety to different degrees of thickness in the ratio of 1, 2, 3, 4: particular care was taken to give to their principal surfaces a perfect parallelism, and the highest polish possible. The following are the deviations which they successively produced in the index of the galvanometer under the action of the same radiation, namely 30°:

Each number in the second column is deduced from fifteen observations: the quantities registered under the denomination of forces, representing in this particular case the respective temperatures or quantities of rays transmitted, have been calculated according to the principles with the exposition of which we concluded our general observations. The force or temperature answering to 30°, as given by the table of intensities, is 35·3; now, by dividing each number of the third column by 35·3, we shall obtain the ratios of the transmitted rays to the incident rays. The difference between each of these quotients and unity will give the corresponding loss; that is, the proportional part of


text:
Author:Henry Christopher Mance

Works

 * "Measurement of the Internal Resistance of a Multiple Battery by Adjusting the Galvanometer to Zero," in Proceedings of the Royal Society of London, Vol. 19, (1870 - 1871), pp. 248-252

title: Author:Henry Christopher Mance


text:
Author:Arthur Scott Bailey

Works
The Tale Of Cuffy Bear

The Tale Of Frisky Squirrel

The Tale Of Tommy Fox

The Tale Of Fatty Coon

The Tale Of Billy Woodchuck

The Tale Of Jimmy Rabbit

The Tale Of Peter Mink

The Tale Of Sandy Chipmunk

The Tale Of Brownie Beaver

The Tale Of Paddy Muskrat

The Tale Of Jasper Jay

The Tale Of Rusty Wren

The Tale Of Old Mr Crow

The Tale Of Solomon Owl

The Tale Of Jolly Robin

The Tale Of Freddie Firefly

The Tale Of Dickie Deer Mouse

The Tale Of Ferdinand Frog

The Tale Of Buster Bumblebee

The Tale Of Betsy Butterfly

The Tale Of Kiddie Katydid

The Tale Of Major Monkey

The Tale Of Timothy Turtle

The Tale Of Miss Kitty Cat

The Tale Of Daddy Longlegs

The Tale Of Benny Badger

The Tale Of Grandfather Mole

The Tale Of Bobby Bobolink

The Tale Of Grumpy Weasel

The Tale Of Chirpy Cricket

The Tale Of Henrietta Hen

The Tale Of Pony Twinkleheels

The Tale Of Mrs Ladybug

The Tale Of Turkey Proudfoot

The Tale Of The Muley Cow

The Tale Of Grunty Pig

The Tale Of Master Meadow Mouse

The Tale Of Nimble Deer

The Tale Of Snowball Lamb

The Tale Of Old Dog Spot

title: Author:Arthur Scott Bailey


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 Sisson, and Bergen, whose scale made 32° Fahrenheit = 6° B., and 212° Fahrenheit = 174° B. Michael Christian Hanow, of Danzig, adopted a scale in which two degrees Fahrenheit equaled one degree H.; having observed in 1740 that the alcohol in a Fahrenheit thermometer fell to ten degrees below zero, he immediately devised a scale in which the zero-point was lowered ten degrees.

These objectionable imitations of Fahrenheit's thermometers brought the genuine ones into evil repute, but the latter outlived their rivals and Fahrenheit's scale is the popular one wherever English is spoken. The weakness of Fahrenheit's scale was the three fixed points somewhat vaguely defined.

Thermometers for a special and limited use were manufactured about 1727 by John Fowler, Swithin's alley, near the Royal Exchange, London; these were adapted to the cultivation of hot-house plants, being graduated to indicate degrees most "kindly" to given plants. The instruments varied in length from 18 inches to 4 feet, and the stems were marked


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 NOTE AS TO THE REFERENCE LETTERS

ordinary Latin capitals and minuscules were selected as being the more suitable for the diagrams, owing to their upright character, yet the corresponding small italic letters have been employed in the text because of their greater conspicuousness. In case this should cause inconvenience to any reader of other than English nationality, who is not quite familiar with both these forms of small letters, the following list of the two sets of equivalent characters may be found useful:—

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TRUST that the student of Optics who casually scans the pages of this work for the first time, will not be alarmed by the complicated appearance of some of the formulæ employed in the course of working out the conclusions, and therefore infer that it is necessary to be highly trained in mathematics in order to follow the lines of reasoning employed. For such is not the case; all that is really necessary in the mathematical equipment of the student being an easy acquaintance with the ordinary manipulations of Algebra, together with a clear grasp of the Binomial Theorem, the chief propositions of Euclid, and the rudiments of the Differential Calculus. That granted, and given some instinct for the practical application of what he knows, then he will have no insuperable difficulty in following this work from cover to cover.

The greater part is easy compared to the numerous problems and theorems which the average university student is called upon to solve, and which in so many cases are treated as of purely theoretical interest. After all, is not that the truest and most fruitful teaching of mathematics which fully recognises the mutual support between theory and practice ? Otherwise it is but natural if the student cleaves to the one and despises the other.

I do not wish to imply that there is no scope for the employment of the highest mathematical skill in optical science; for, on the contrary, there are numerous problems in connection with the corrections of the third order of approximation, merely glanced at in Section XL of this work, which pre-eminently call for the elucidating and marshalling influence of some clear-headed mathematician who shall be thoroughly familiar with the properties of lenses from practical acquaintance, and not only from the theoretical point of view. The closer approach to perfection in the optical combinations of the future will lie in the more thorough elimination of the corrections of the third order, and in some cases of the fourth order, and the most highly trained mathematical skill, if it should ever deign to busy itself in this


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90

a healthy child who has been well trained, nothing appears more easy than to be happy; to a child who has been badly trained, whose infant years have been neglected or motherless, nothing appears more difficult. There is often something in the bodily constitution, too, which stands in the way of individual happiness, without our being sensible of any actual disease; and the mother ought to watch carefully every symptom of this nature as indications of growing evil, which may frustrate much of the good she naturally looks forward to in the future experience of her child. She ought especially to observe, if, when the family group are loudest in their mirth, there is one who falls back from the cheerful circle, and who, instead of catching the natural infection of laughter and glee, sits moping alone, with cloudy brow, and drooping head, as if incapable of partaking in the general feeling. Such a tendency as this, is generally to be attributed to some bodily indisposition, of which perhaps the child is not aware; but it may also arise from a peculiarity of temperament, only to be accounted for upon the principle that there are diseases of mind, as well as body, the seeds of which are inherent in our nature.

If, in order to correct a melancholy tendency discoverable in infancy, the child is harshly treated, punished, scolded, and compelled to play, it is needless to foretell the utter ruin of its temper, and probably of its moral character altogether; for never yet was melancholy expelled except by the substitution of cheerfulness; and never yet was a child made cheerful by harshness and compulsion.

While thinking how much a kind and judicious mother can do toward correcting the melancholy temperament of her child, the heart aches for those who have no mother, who, in their moments of sadness and sorrow, are subjected to the ridicule of their companions, and who consequently

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Rh bear about with them, in their intercourse with others, a wounded spirit, smarting at every touch. The premature and excessive suffering of such children when left to the injudicious treatment of their companions, or to persons who pay little regard to what they experience, generally renders them selfish in their feelings, and in their tempers bitter and revengeful. They are selfish, upon the natural principle of caring for nobody, because they think nobody cares for them; and bitter and revengeful, because, being wrapped up in self, and that self, as they imagine, deeply injured, they are perpetually tempted to pay back, in their treatment of others, some portion of the suffering they endure.

It must be granted, however, that this description applies only to extreme cases; but still there are many degrees of the same evil to be found existing in the world; and it is well for mothers to consider the extent to which their children are capable of suffering from want of attention rightly exercised, in order that they may form a higher estimate of the real benefits placed within their power to dispense.

It was the custom with many well-intentioned parents, some fifty years ago, to bring up children under a mistaken notion of rooting out evil, before good could be introduced; of breaking the natural will, crossing natural inclination, and subduing pride by constant mortification. Yet, notwithstanding the various modes of discipline adopted in carrying out this notion, people were just as self-willed, as determined to please themselves, and as proud, as they are now. It has by decrees become evident to persons of common sense, that such violent measures are not adapted to produce the desired effect. Indeed, some of us have gone so far as to believe, that pride is no more likely to be eradicated by constant mortification, than appetite is likely to be destroyed by a scanty supply of food. Inclination, too, whenever it is crossed for the mere sake of punishment, seems to grow and acquire force under the infliction; just as a delicate frame gains strength by the application of a tonic; or, if in a few instances harsh treatment does succeed in breaking what is called the natural will, it can

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92 only be by destroying the power to will, which is in reality to render the moral character contemptible and weak.

But why should the mother, in her moral training, allow weeds of evil growth to gain the ascendency, before she has planted flowers? Let her begin by keeping alive the wholesome glow of cheerfulness throughout the domestic atmosphere, and melancholy will not dare to spread her gloomy pall over a scene so radiant with joy, as that which is presented by a happy and well-regulated home.

After all, however, it is possible that we do not value cheerfulness as we ought. We look upon it as an ordinary something which belongs to common minds—the property of the milkmaid, the housewife, or the husbandman. Yet, granting all this, we must still acknowledge it to be something which kings can not purchase, though in all probability they often gladly would. And does not the fact of cheerfulness being generally considered as the reward of labor, teach us a pleasant and a useful lesson—that cheerfulness may be procured by industry—by always doing something, and by always having something to do?

It is in this manner, chiefly, that the cheerfulness of infancy is maintained. Childhood is full of activity, and rich in resources and therefore we make a great mistake when we lavish too much of the means of enjoyment upon young children. It is a little later in life that we begin to want the means of being happy; that the pulse of natural joy throbs languidly; and that we seek excitement, to warm us into life and feeling. Nor is it in childhood alone that we see the benefit of cheerfulness, for with plenty of resources, and a cheerful disposition, persons more advanced in life are placed almost beyond the reach of disappointment. It is the dull, the flat, and the unoccupied, who hang their happiness upon an evening party, and who are always dependant upon some extraordinary excitement for breaking the monotony of their fruitless lives. "No one," said Miss Hamilton, "under the necessity of earning their daily subsistence, is in any danger of dying either of grief or love." And certainly that constant occupation which promotes cheerfulness, is the surest protection against diseases of the mind, and especially against melancholy.

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Rh While seeking the happiness of children, however, we must not be so forgetful of their good, as to pay no regard to the kind of happiness which is to be the object of their desires. We must not forget that we are all in a state of progression, and that children especially are only commencing what time will mature. Why then should we seek for them a low kind of happiness, such as the indulgence of appetite, or the mere gratification of the senses in any other way; since no circumstances in after life, no development of character, and no cultivation of those senses, can render such happiness intense in proportion to our improved facilities for obtaining it. Thus a child who has imbibed the idea that eating and drinking constitute the highest enjoyment, stands in the unfortunate position of having nothing more to gain; because no cultivation of the sense of taste can enlarge to any considerable extent the pleasure it is calculated to afford.

It is not thus with the pleasures of the mind. Ever progressing, ever enlarging the sphere of its enjoyments, human nature is capable of advancing onward, until it attains an approximation to the Divine; and the higher the range of thought and feeling which it occupies, the purer is the enjoyment of which it participates.

In this intellectual progress, mothers have more to do than most women seem to be aware; because it is peculiarly their province to render the path of learning lovely and attractive, and thus to associate feelings of happiness with the acquisition of ideas, the prosecution of study, and the general improvement of the mental faculties. Mothers are apt to be startled at the idea of educating their children, as if education consisted in nothing but the routine of daily lessons, or as if the extreme of intellectual culture was dependant upon them. Happily, however, theirs is a labor of love, rather than of tasks, and it is simply by, and in, this love, that they are called upon to throw the whole weight of their influence, of their powers to charm, to amuse, and fix attention, into the scale of intellectual improvement; so that nothing shall be wanting on their part to render their children not only willing, but happy, to go on from step to step, until they learn to love intellectual pleasures for their own sake alone.

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94 That a mother may effectually do this by the exercise of good feeling and tact, without being herself fully instructed in every branch of learning and science, is evident from the experience of different families; for we do not want beautiful instances of simple-hearted, unpretending mothers, not highly-gifted by nature in any way, who send their children to school in such a state of mental preparation, as to render it a pleasure to conduct their education to its utmost limits.

"Many ladies," says Miss Edgeworth, "show in general conversation the powers of easy raillery joined to reasoning unencumbered with pedantry. If they would employ their talents in the education of their children, they would probably be as well repaid for their exertions, as they can possibly be by the polite but transient applause of the visiters to whom they usually devote their powers of entertaining. A little praise or blame—a smile from a mother or a frown—a moment's attention, or a look of cold neglect—have the happy or the fatal power of repressing or of exciting the energy of a child, of directing his understanding to useful or pernicious purposes. Scarcely a day passes in which children do not make some attempt to reason about the little events which interest them, and upon these occasions a mother who joins in conversation with her children, may instruct them in the art of reasoning without the parade of logical disquisitions."

It is not then extraordinary powers which are wanted for this purpose, but the. right exercise of those peculiar talents with which women are naturally endowed, combined with that earnest love on the part of the mother, which enables her to pursue unwearied the instruction of her children in all common things, and to watch every opportunity for blending information with enjoyment.

I would not, however, by any means neglect those auspicious occasions which occur in every family, of throwing off all restraint, and giving free vent to the overflow of affectionate and unbounded joy, The return of some member of the household, the arrival of beloved friends, birthdays and other seasons of festivity, afford ample scope for these outbursts of natural feeling, which ought to be encouraged as a means of keeping up the natural and healthy

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The Moths of the British Isles/Chapter 7

This species has the fore wings of the male brownish clouded and suffused with ochreous; there is a white patch at the base, and some white marks including three spots towards the apex, on the outer marginal area; two black cross lines, the first inwardly and the second outwardly, edged with white; the space between the lines is sometimes clouded with whitish, and there is an almost central black -shaped mark. Hind wings tawny with a black central line, some brownish marks beyond, and sometimes two white spots at the upper angle. The female is much larger in size, without ochreous suffusion on the fore wings, and the hind wings have the ground colour whitish. It varies in the tone of the brown colour, and, in the male, in the amount of ochreous suffusion (Plate 65).

The eggs are laid in rows, generally two deep, on a birch twig. At first they are greenish, but soon change to brownish olive or shining purplish brown.

When young the caterpillars cluster together on the twigs, as shown on Plate 64. They are at first black with glossy dots, and later, greenish, but still dotted with black. After the third skin change, they are without the black dots, and the colour is then pretty much that of the mature caterpillar, which is green, rather whitish on the back, and with a dark green central line; a series of seven creamy oblique stripes along the sides, and on the sides of the first three rings there is a whitish stripe broken at the divisions; these markings are often edged with dark green; on the eleventh ring there is a somewhat horn-like prominence, striped with creamy white, and below it a yellow stripe; the spiracles are white, ringed with black. Head small, paler green, with whitish marks. Feeds on birch, from late May to July. Alder, sallow, and lime have also been mentioned as food plants.

The rough, blackish, or sooty-brown chrysalis is enclosed in a coarse netted cocoon, dark brown in colour, and more or less covered with moss, leaves, or other material, among which it is spun up, generally on the ground, but sometimes just under the surface. Assisted by the points on the rings of the body, the chrysalis is able to work itself partly out of the cocoon, and this it does some days before the moth emerges.

The moths usually emerge in late March and in April, earlier or later in some seasons. They do not always come up the year after pupation, but often remain two or more winters in the chrysalis.

The males fly in the sunshine, and are very strong on the wing; the females are not active until dark. This sex has been found resting on the twigs of birch, also on heather, and occasionally on a tree trunk. The males "assemble" freely to a freshly emerged female. The species inhabits the more open parts of woods and forests, moors and hillsides where birches flourish. It is probably more plentiful in its Scottish localities, such as Rannoch and Forres, than elsewhere, but it occurs also in Aberdeenshire, Kincardineshire, and Argyllshire. In England it seems to be not uncommon in Wyre Forest, Worcestershire, and the Reading district in Berkshire. It used to be so plentiful in Tilgate Forest, Sussex, that over a hundred males were brought to the net in one day by a bred female put down to allure them. This happened some fifty years ago, and compares curiously with a record of one male attracted by a female in Tilgate Forest, April 13, 1869. Other localities in Sussex that have been mentioned are St. Leonard's Forest and near Petersfield; it has also been found in Herefordshire and in some parts of Suffolk. Distributed over Central and Northern Europe, the range extending to North Italy.


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Rh tone of youthful minds; for as an hour now and then of absolute romping does infinite good to the bodily health, so an hour now and then of unrestrained and absolute merriment does equal good to the spirits and characters of children.

In a rude and ill-regulated family, it is to be feared that such seasons would be marked by turbulence and disaster, beyond what could be rendered conducive to much enjoyment, especially on the part of the older members; but I am supposing the case of a well-regulated family, so trained by the mother, and so under the influence of delicate, affectionate, and generous feelings, that their wildest play would not be rude, nor their loudest mirth offensive.

It seems to me one of the peculiarities of English character not to know how to manage enjoyment; while our neighbors on the continent sometimes manage it a little too much. Those elaborate or costly presents by which they are so fond of creating a beautiful surprise, those birthday scenes got up with so much machinery of contrivance, and those periodical displays of generosity and affection, though admirably adapted to figure in a book, have a little too much make-believe about them, to be exactly suited to the reality of English habits. Besides which, there always hangs about an English heart a certain dread of failure, a horror of being committed in an act of folly, and a shrinking from ridicule, which greatly lessen the number of our enjoyments, and often cast a shadow over the gayety which might otherwise be both harmless and refreshing. There is also, it must be confessed, a some thing desperate and extreme about the English character when strongly excited and destitute of restraint, which seems to render greater restriction necessary in a social point of view, than is required by people ox some other countries; yet I can not but think that much of this, and much that we see and grieve over in the conduct of our countrypeople abroad, arises from the want of better regulation in private families, of higher aims in the union of taste with feeling; but chiefly from the absence of all care that the happiness of children should be encouraged to the utmost extent which good order will allow, but at the same time blended with a little more nicety as to the choice of

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96 means, a little more tact on the part of mothers, sisters, and mistresses of families, a little more taste—in short, a little more of the true poetry of life, so that the general tone of the mind, even in its joyous moments, shall be in strict harmony with good feeling.

Were this the case, I believe we should all live in less fear of youth overleaping the accustomed barrier of good manners, so as to run riot in its excess of merriment; and while by the same means we should learn to suffer less from the dread of being ridiculous, we should be more generally cheerful, and, upon the whole, more happy than we are.

And to whom are we to look for improving at once the manners and the morals of social life in this most delicate point, but to the mothers of England? Servants and nurses, in whose company so many children are allowed to play without restraint, and in no other; they are not fit for such a task. Fathers are seldom present, and when they are, they want the nicety and the tact to manage the minute affairs of domestic life, and especially those of individual feeling. It is to mothers then, alone, that we can look for the improvement so much needed here; ad with all woman's taste and tact, her quickness of feeling, play of fancy, minuteness of observation, and facility of adaptation to circumstances; with all a mother's love in addition to these, she wants only a higher sense of a mother's duty to convince her that the joyous moments—the holy days of mirth which her children are permitted to enjoy, are those which she, above all other human beings, has the privilege of sharing, and, at the same time, of converting into lasting good.

There is no reason why children should be either selfish or vulgar in their mirth; yet how many do we find who can be well-behaved in what is called company, and yet when let loose to play, are a disgrace to their parents; who, perhaps, from never associating themselves with their children's merriment, but having been accustomed to send them always into the nursery to play, and into the company of servants to run wild, having imposed upon them a sort of artificial restraint, which makes them decent and tolerable only while it lasts, but leaves them, whenever it

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Rh is withdrawn, perfect monsters of rudeness, turbulence, and disorder.

It is not difficult to foresee that such children will grow up with a constant liability to commit themselves in after life, which, under the most favorable circumstances, will mark their habits with a want of ease and of true refinement; while, under unfavorable circumstances, it will not improbably be the means of leading them into egregious folly, gross excess, or fatal error.

I would not willingly be supposed to forget that religious principle alone is sufficient to preserve even such persons as are here described from the extremes alluded to; but I am also aware, that even in religious characters, there are sometimes strange anomalies, deviations from true taste, and even unconscious offences against good feeling, which do incalculable harm to the interests of religion; and I am therefore the more earnest in writing on this subject, that mothers should begin in time by laying the foundation of lovely, good, and happy characters, at once.

We sometimes find among truly excellent persons, a painful and unnatural kind of dread of being too cheerful; and where the pleasures of childhood have been wholly neglected, where buoyant spirits have been allowed to run and riot without a mother's care, there is unquestionably great danger of the barrier of propriety being broken through in after life by the indulgence of cheerfulness. But how deeply it is to be regretted, that that particular state of mind which is in reality the most truly happy, should be deterred by fear, from exhibiting itself before the world in its natural character of healthy cheerfulness, and thus give cause for an opinion, too frequently entertained, that religion is a gloomy thing! If by no other reason the pious mother can be convinced of the importance of her influence in this particular sphere of duty, surely it is sufficient, if by sharing with her children in their harmless mirth, and teaching them how to be happy without offence to God or man, she can beautify their characters in after life with more of those graces of mind and manners, which are at once attractive to the world, and honorable to the cause of religion.

As the first and surest means of promoting individual,

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98 as well as social happiness, I would propose the cultivation of a spirit of love. The more we love, the less our thoughts and interests are centred in self; and consequently the less we suffer from all those little personal slights, vexations, and disappointments, which so often imbitter the cup of life. The more we love, also, the more we forgive; and to whom much is forgiven, the same loveth much; so that nothing is more true, than that love begets love in return. Thus, then, our energies are drawn out into those kindred charities, which, whether given or received in the true spirit of generous affection, have power to lighten every burden we have to bear, and to sweeten every draught of which we have to drink. The more we love, the more we enjoy the inestimable privilege of being able to ask a blessing upon what we desire, and upon what we do; because we can neither lie down at night, nor rise to the duties of the day, without bearing in our hearts the remembrance of that sweet fellowship, which binds together the whole human race as one family, under the protection of our Father who is in heaven.

How little is understood of the real value and right exercise of love, by those morbid miserable beings, who fix their whole hopes of happiness upon one, or two, or many, and think they are loving, while they are only thirsting to be loved—only waiting in anxious and fretful expectation for evidence that they are so; or recoiling from the world with disappointment and spleen on every cause for suspicion that they are not. Such persons generally keep a strict account against society, of what they consider due to themselves, as well as of what they receive. Yet they forget to compare it with another account—with what is due from them, and what they actually give.

But there is no calculation, and there needs no account, on the part of those whose hearts have been imbued in early childhood with the true spirit of love. To such it becomes as the very breath of life, for without being able to love, they would pine and wither. If, in the interchange of kind offices they occasionally find themselves neglected, what is that to them? In their love they seek only the good and the happiness of others, and that is generally more or less in their power to promote. If the beings

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The Moths of the British Isles/Chapter 8

In a general way the fore wings of the male may be described as purplish grey, suffused with rosy or with tawny shades; a reddish cloud, black marked above, at the tips of the wings; the outer margins are more or less whitish, and there is a whitish patch about the middle of each wing, in which is an eyed spot; the hind wings are tawny, with a central eye spot and a blackish band towards the outer margin. The female has all the wings pale purplish grey, with whitish bordered outer margins; markings much as in the male, but the central area of the hindwings is more or less whitish. There is some variation in the ornamentation; occasionally the white markings are of large size, or, on the other hand, may be almost or quite obscured. Very rarely the eye-spots are absent from all the wings (ab. obsoleta, Tutt), and sometimes they are of abnormal shape. Now and then specimens of the female sex are dark in colour, with red bands, and Barrett mentions an example of this sex smoky black in colour, with still blacker markings (Plate 66).

The olive brown, clouded greyish eggs are laid in neatly arranged batches around the stems or twigs of plants; I once found a batch in North Devon on a loose piece of rock. The caterpillar when full grown is bright green, with black markings; the warts from which blackish bristles arise are yellow, sometimes pink or blackish. In an early stage it is black, with an orange line low down along the sides; later on it is still black, but ringed with orange. It feeds in June, July, and August on many kinds of plants, among which may be mentioned heather, bramble, sallow, sloe; also meadow-sweet (Spiræa ulmaria) and purple loose-strife (Lythrum salicaria).

The curious cocoon formed by the caterpillar (Plate 67) is so constructed at the narrow end that the moth on emergence can easily pass through; after the insect's escape, the converging fibres forming the "door" spring to again, and the point of exit looks pretty much as before the moth had pushed through. This kind of opening can only be worked from the inside, therefore enemies from without are unable to effect an entrance.

The moths are out in April and May, and the males may be seen on sunny days flying at a great pace over heaths, moorlands, and mosses, also about the borders of woods. The female flies at night, but it may occasionally be met with resting on heather or other herbage in the daytime. A freshly emerged female moth will, as a rule, attract as many specimens of the opposite sex as one would care to take; all that one has to do is to take her in a box to some likely spot, and there await the coming of the males.

The species seems to be generally distributed throughout the British Isles, but is commoner in some parts than in others, and apparently rare in portions of the Midlands.

The distribution abroad extends through Europe to North Asia Minor and Armenia, and to Siberia, Amurland, and Ussuri.


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Rh by whom they are surrounded, and perhaps even the nearest and the dearest, are not all they desire, it is the noblest exercise of love to forgive, and the next to endeavor to improve. If also, in the exercise of affection, they meet sometimes with but little or no return, they accept the rebuke as from a Father, who, in chastening those whom he loves, has appointed such means for leading them into closer self-examination, into stricter watchfulness, and more faithful endeavors, in order that no fault indulged, no opportunity neglected, and no faculty unemployed, may stand in the way of rendering the service he has enjoined, as a duty we owe one toward another, more acceptable in his sight.

Such then is the effect of an early and consistent exercise of the spirit of love, extending in the first place to all beneath the paternal roof, and afterward throughout the varied intercourse we hold with society—a spirit which, where it is rightly exercised has no tendency to blind us to the faults of others, or to lead us to undervalue those proofs of affection which are really directed to ourselves; but which creates around us a kind of genial atmosphere, too clear and bright for the weeds which grow around our path to remain undiscovered; yet, at the same time so pure, healthy, and invigorating, as to stimulate to eager cultivation of the flowers, secure in the confidence that they will abundantly repay our care.

Nor should we forget, in the contemplation of this subject especially, that beautiful harmony in the order of Providence, by which all that is best adapted to produce good to others, is in reality most conducive to our own happiness. Had we been created only to feel happy in the exercise of those passions which dissever families, and break asunder the bonds of society, how different would have been our situation on earth! But in the benign commandment of the Savior to his disciples that they should love one another, in making this love even the test of their fellowship with him, we recognise at once a principle, which, above all others, has power to bless and to bind on earth, while it constitutes a passport to the blessedness and the union of heaven.

Next in degree to the exercise of the afflictions, as a

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The Moths of the British Isles/Chapter 9

The British species belonging to this family, with one exception, have the tips of the fore wings pointed and curved downwards, forming a sort of hook, hence the English name Hook-tips. The exception is Cilix spinula, a round winged moth, not at all like other members of the family, but its caterpillar is very like others of the group.

The bristle and catch arrangement for locking the wings is present in all the species, but the tongue or proboscis is absent, or practically so. The caterpillars are not furnished with anal claspers, therefore have only fourteen legs, that is, six true legs and eight false legs (pro-legs). The last ring of the body is more or less tapered, sometimes terminating in a point; the back is roughened with raised spots and warts, or humped. They feed on the leaves of trees and bushes, usually exposed, and they pupate in a silken cocoon, spun up between leaves, or in a folded leaf, of the food plant.

Of the eleven species occurring in the Palæarctic Region, seven are European, and six of these are found in the British Isles.

The fore wings are brown, whity brown, or whitish; the central area is crossed by three blackish wavy lines, a blackish blotch in the third line and two blackish dots between it and the second line; beyond there is a dark brown, or reddish-brown curved line from the tip of the wing to the inner margin. Hind wings similar in colour to the fore wings, but paler on the front area; crossed by five wavy dusky lines, sometimes not well marked except on the inner margin; generally, there is a black central dot. The paler forms have a dusky shading on each side of the curved line on the fore wings.

The egg is yellow freckled with orange, chiefly at one end. Caterpillar green, the back reddish-brown, except towards the black-marked yellowish head; two conspicuous warts on rings two to five, and less noticeable raised spots on the other rings, all bearing hairs. In a younger stage it is blackish, with white marks on the fourth and seventh rings; later it becomes greenish below, and the markings on the back of rings four, seven, eight, and ten are whitish or creamy. Until nearly full grown it usually lives on the underside of a leaf, the edges of which are turned over and held down by silken threads; sometimes it may be seen on the upper side of a leaf under a slight web. It feeds chiefly on birch, but is occasionally found on alder, in June and July, and in September and October, and may be obtained by searching or by beating, but the former, although perhaps slower, is much the better method. The moth is shown on Plate 68, and the early stages on Plate 69.

The species is widely distributed, and seems to occur, sometimes commonly, wherever there are birches, especially of bush-like growth, in most English counties and also in Scotland. In Ireland it appears to be somewhat local and scarce.

The general colour of this species is brownish; the fore wings are slightly tinged with ochreous and speckled with minute violet-tinged silvery scales; between the first and second brown lines there is an irregular ochreous brown mark enclosing yellowish spots; the violet-tinted glistening scales are most in evidence on both sides of the black mark before the outer margin. Hind wings similar in colour to the fore wings; crossed by two brown lines, the second with an ochreous brown blotch above it (Plate 68).

Caterpillar, yellow freckled with brown; clouded with brown on first three rings; a reddish brown irregular stripe runs along the sides and upwards towards middle of the back on rings five, six, eight, and nine; a double-pointed hump on the back of ring three, the points tipped with yellow. Head notched on the crown, dotted and clouded with brown. It feeds on the small-leaved lime (Tilia parvifolia), and may be found from July to September and even later. I have not seen a living caterpillar of this species; the above short description has been drawn from an inflated skin (Plate 69).

The only British locality for this species is the Leigh Woods near Bristol, where it was first met with in 1837. It is, however, very rare and difficult to obtain. Abroad it ranges through Central Europe to Livonia, Southern Sweden, and to Northern Italy. On the Continent the caterpillar feeds on the foliage of other trees than lime, and there are two broods in the year.

The male is of an ochreous-tinged brown coloration; all the wings are crossed by two slender deep ochreous lines, and have two obliquely set, almost central, black dots; outer margin of fore wings often blackish, marked towards the tip; the hind wings are deep ochreous on the front marginal area. Fore wings of the female paler, and the hind wings ochreous yellow; the cross lines on the latter often lost in the ground colour (Plate 71).

In freshly emerged male specimens the brown is sometimes purplish tinged, and in some examples of the same sex the hind wings may be described as ochreous, with brown bands. The female occasionally has the fore wings tinged with greyish, and the hind wings are sometimes banded with brown, especially on the inner marginal area.

The caterpillar is ochreous brown with a double-pointed hump on ring three, a yellowish diamond on the back of rings five to ten; the front and hind rings are brown, more or less tinged with purple; yellowish lines, shaded below with purplish brown, on the sides meet on the back and form an edging to the diamond mark. The figure on Plate 70 shows the caterpillar in its usual resting attitude. It feeds on oak.

A widely distributed species in the southern half of England, but not especially abundant in any locality, and not known to occur north of Lincoln.

Fore wings pale fulvous or ochreous brown, with two paler cross-lines on all the wings, space enclosed by the lines darker brown; a black or blackish central dot, and before the brownish outer margin there is a pale line ending on the tip of the wing. The hind wings have an obscure dusky central dot placed in the upper edge of the band, and usually there are two brownish bands on the outer marginal area, but these do not extend to the front margin. Except that the female is generally larger, and the antennæ are simple, the sexes are much alike (Plate 71).

This species is best distinguished from binaria by the dark bands, and the straighter second line. The central dots are less trustworthy characters, because summer specimens of the present species often have two of these spots on the fore wings (var. æstiva, Spr.), and in occasional examples of binaria the lower central spot of the hind wings is absent. As a rule, however, the central dots are more conspicuous in binaria than in cultraria. The egg is yellowish, tinged with reddish at the ends and along the sides. The caterpillar is somewhat similar to that of the last species, but the hump on ring three is smaller, and the side lines and diamond mark are whiter. It may be found in June and July, and again in September, and even in October in some years. It feeds on beech (Plate 70).

This species is found where beech trees occur, preferably on a chalky soil, in the counties of England from Norfolk southwards. The male may often be seen in May, flying around the beech trees or neighbouring bushes, in the sunshine; or both sexes may be caused to leave their resting places among the foliage by tapping the boughs.

Its range extends through Central Europe to Asia Minor.

The name Scallop Hook-tip given to this species by Moses Harris in 1775, doubtless referred to the ragged outlines of the fore wings. These wings are pale brown in colour, freckled and clouded with darker tints, and crossed by two dark-brown lines; the central dot is black, but often minute; fringes white, chequered with brown. Sometimes the freckling is heavy and the clouding very dark, becoming almost black on the outer margin; such specimens seem to be referable to var. scincula, Hübn. In another form the fore wings are ochreous brown, with very tiny freckling and only light clouds on the upper part of the outer margin. The hind wings in all the forms are pale whitish brown, with a black central dot, and brown marginal line; in the darker specimens these wings are clouded or suffused with dark brown (Plate 71).

The egg is pale yellowish when laid, but changes afterwards to reddish. The full-grown caterpillar is pale brownish, marked with darker or reddish brown on the back and sides, and raised spots; there are double-pointed humps on rings two and three, and a similar but smaller elevation on ring eleven. In the younger state the caterpillar is blackish, with whitish marks on the fourth, seventh, and eighth rings, and some white dots on the end rings. It feeds on the upper surface of the leaves of birch in June and July, and again in August and September.

Chrysalis, reddish brown, the ring divisions blackish grey; powdered with whitish, and appearing as though dusted with flour. Attached by the anal spike to the interior of the silken web-like cocoon. In the Figure (Plate 69) the pupa is shown hanging from the ruptured cocoon, upon the covering leaf of which a half-grown caterpillar is depicted.

The moth is out in May and June, and a second generation appears in August. It is not uncommon in most birch woods, and on heaths and commons, where birch flourishes; but the perfect insect, which rests on leaves and twigs of trees and bushes, and the herbage under them, is not so frequently or so easily obtained as the caterpillars. The latter may be searched for in the daytime, or they may be dislodged by beating.

Widely distributed throughout England, but local or scarce in Lancashire and Yorkshire and northwards; also, according to Barrett, in Devonshire and in the fens of Norfolk and Cambridge. It occurs in the Clydesdale district, Ross, Argyllshire, and Sutherland in Scotland; and in Ireland it seems to be widely spread and common in some localities.

Probably in reference to the grey-brown oval blotch on the middle of the white fore wings, this moth was known to the older entomologists by the English name of "Goose-egg." On the blotch, however, there are silvery marks on the veins, and below it (often attached) there is a blackish blotch with some bluish silvery scales upon it. These markings probably suggested to Haworth the name Chinese Character by which it is commonly known (Plate 71).

The caterpillar is reddish brown, with a darker line along the back, and a paler patch on rings three to five, extending as a narrow stripe to the dark-brown spiked tail; two raised warts on rings two and three, with a white dot between the hinder pair. Head darker brown, paler in front. It feeds in June and early July, and in September and October, chiefly on hawthorn and sloe, but it will also eat apple and pear. The chrysalis, which is enclosed in a brown, rather tough, silken cocoon, spun up among leaves or under loose bark, is greyish on the wing covers, and reddish on the body.

The moth is out in May and early June, and again from late July well into August. Sometimes it may be seen resting on a leaf in a hedgerow. When disturbed in the daytime, which may happen where one is beating the bushes, it falls, rather than flies, to the ground. At night it may be netted as it flies along the hedgeside or wood borders in almost every county of England and Wales. In Scotland its range seems not to extend north of Clydesdale. Kane states that it is "widely spread, but not generally at all numerous" in Ireland.


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 was patterned after it), and was the first that could be used for all liquids.

In the fifth paper Fahrenheit describes his invention of the thermo-barometer, based on the fact that the boiling-point of water is influenced by barometric pressure. Boyle had observed the lowering of the boiling-point under the receiver of the air-pump, but Fahrenheit was the first to discover the principles of hypsometry.

Fahrenheit's publications are few in number and very brief, but they show him to have been an original thinker, and his great mechanical skill in working glass enabled him to carry out his designs. His account of the thermometer is of so great interest that I give it entire.

"The thermometers constructed by me are chiefly of two kinds, one is filled with alcohol and the other with mercury. Their length varies with the use to which they are put, but all the instruments have this in common: the degrees of their scales agree with one another and their variations are between fixed limits. The scales of thermometers used for meteorological observations begin below with 0° and go to 96°. The division of the scale depends upon three fixed points which are obtained in


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 the following manner: The first point below, at the beginning of the scale, was found by a mixture of ice, water and sal-ammoniac, or also sea-salt; when a thermometer is put in such a mixture the liquid falls until it reaches a point designated as zero. This experiment succeeds better in winter than in summer. The second point is obtained when water and ice are mixed without the salts named; when a thermometer is put into this mixture the liquid stands at 32°, and this I call the commencement of freezing, for still water becomes coated with a film of ice in winter when the liquid in the thermometer reaches that point. The third point is at 96°; the alcohol expands to this height when the thermometer is placed in the mouth, or the arm-pit, of a healthy man and held there until it acquires the temperature of the body. If, however, the temperature of a person suffering from fever, or some other disease, is to be taken another thermometer must be used having a scale lengthened to 128° or 132°. Whether these degrees are high enough for the hottest fevers I have not examined; I do not think, however, that the degrees named will ever be exceeded in any fever.

"The scales of such thermometers as are


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 used for determining the boiling-points of liquids begin also at 0° and run up to 600°, for at about this temperature mercury begins to boil. To increase the sensitiveness of thermometers they are made with cylinders instead of spheres, so that a larger surface will be more quickly affected."

Fahrenheit then gives a full account of his method of filling thermometers with liquids, a practical feature not necessary to detail in this place. The fever thermometers were known as "Pyranthropometers."

While these scanty records are all given us by Fahrenheit himself, other details are furnished by contemporary writers; Christian von Wolf describes the instruments given him by Fahrenheit thus:

The two thermometers had cylinders in place of spheres and were filled with colored alcohol. The cylinder of one was one and three-eighths inches long (12 inches to a Paris foot), thirteen sixty-fourths inch in diameter, and the lower portion ended in a sphere; the tube was six and eleven-sixteenths inches long. The scale was six and seven-sixteenths inches long and had 26 degrees, each of which was divided into four. The second degree on the


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Index to Volume LIV. Stapleton, Thomas, D.D. (15S6-1598). . 101 Stapleton, Thomas (l805-1848). . 104 Stapley, Anthony (1590-1655). . .104 Stapley, Sir John (162S-1701). See under Stapley, Anthory. Stark, Adam (1784-1867). . 106 Stark, James (1794-1858). . 107 Stark, William (1740-1770). . . . 107 Starke, Mariana(l762?-l838). . .107 Starkey, Geoffrey (fl.1440). See Geoffrey tbe Grammarian. Starkey, George (d.1666). . . . 107 Starkey, Sir Humphrey (d. 1486). . . 106 Starkey, Ralph (d. 1628). . . . 109 Starkey, Thomas (1782-1819 . . . . 110 Starkie, Thomas (I782-1849) . . . . 110 Starley, James (l83l-1881). . . . 111 Statham, Nicholas (fl. 1407) . . . . 112 Staunford. Sir William (1509-1558), See Stanford Staunton, Edmnnd (1590-1671) . . . 112 Staunton, Francis French (1779?-1825) . 113 Staunton, Sir George Leonard (1737-1801) . 113 Staunton, Sir Georsa Thomas (1781-1859), 114 Staunton, Hervey de (d. 1327) . . .115 Staunton, Howard (1810-1874) . . .116 Staveley, Sir Charles Wllliam Dunbar (1817-1888) . . . 117 Staveley, Thomas (1626-1684) . . . 118 Staveley, William (17S4-1854]. . 119 Stawell or Stowell, Sir John(1599-1662). 120 Stawell, Sir William Foster (1815-1889). . l21 Stayley, George (1727-1779?). . . 121 Stayley. William (d. 1678). See Staley. Stayner, Sir Richard {d. 1662) . . . 122 Stearn. See also Stern and Sterne. Stebbing, Henry (1687-1768) . . . . 123 Stebbing, Henry (1716-1787). See under Stebbing Henrv (1687-1763). Stebbing, Henry (1799-1889). . . . 124 Stedman, Charles (1758-1812) . . . . 125 Stedman, John Andrew (1778-1839) . . . . 125 Stedman, John Gabriel (1744-1797}. . . . 126 Stedman, Rowland (1630?-1673). . . . 128 Steel, Sir Scudamore Winde (1789-1885). . . . 128 Steele, Anne (1717-1778). . . . 128 Steele, Christopher (fl. 1756). . . . 129 Steele, Joshua(1706-l791). . . . 129 Steele or Steel, Richard (1629-1692). . . . 129 Steele, Sir Richard (1672-1729). . . . 130 Steele,Thomas (1788-1848). . . . 137 Steele, Sir Thomas Montague (1820-1890). . . . 138 Steele, William (d. 1680). . . . 138 Steell, Gourlay (1819-1894). . . . 139 Steell, Sir John (1804-1891). . . . 140 Steere, Edward (1828-1882). . . . 141 Steevens. See also Stephens and Stevens. Steevens, Charles (d. 1761). . . . 143 Steevens, George (1736-1800). . . . 144 Steevens, Richard (1653-1710). . . . 148 Stenhouse, John (1809-1880). . . . 149 Stenhouse, William (1773?-l827). . . . 149 Stennett, Joseph (1663-1713). . . . 150 Stennett, Joseph, D.D. (1692-1758). See under Stennett, Joseph (1668-1719 ). Stennett, Samuel, D.D. (1728-1795). See under Stennett, Joseph (1668-1719), Stephanoff, Francis Philip (1790?-1860). . . . 151 Stephanoff. James (1788?-1874). See under Stephanoff, Francis Philip. Stephen (1097?-1154). . . . 151 Stephen, known as Stephen of Whitby (d. 1112). . . . 156 Stephen, Saint {d. 1134). See Harding.

Stephen of Exeter (fl. 1265). . . . 156 Stephen de Gravesend (d. 1338). . . . 156 Stephen Langton (d. 1228). See Langton. Stephen, Sir Alfred (1802-1894). . . . 156 Stephen, Edward (1822-1885) <!@--proofed to here--> Stephen. Sir George (1794-1879) , Stei*en, llenrr John (1787-I8M). Hiophon, James (1758-1832). Stephen, Sir Jameg (1789-1859). Stephen, Sir Jame* Fitzjamea (1829-1894) Stephen, James Kenneth (1859-1892). Se uniler Stephen, Sir Jamea Fitnames, Stepbeni. See aleo SleevBrn end Slereno. .Stephena, Aleiander 1 1757-1821) . Stephen^ Catlierine, (Sunless of Knex <17H ) Slephena, Chu-les Edward (1821-1892) Stephen)^ Edward (d. 1T06). , Stephens, Kdward Bowrtng (181G-1S81) Stephens, GeorgB(l800-ISSl>. Stephenn, George (1SI8-1BS5) SCefihena, Henry ( 1795-1874) . Stejihens, Jamei Francis (17^1862) Stcphell^Jaue(lSI3?-18g6) . Stepheni, Jeremiah (lS91-t6aS) . Stephens, John (!. 1616) Stephens, Joseph Rayner ( 1805-1879) Stephens, Nathaniel (1606 ?-1678) . Stephens, Sir PhiHp (1725-1809) . Stephens, Robert (1665-1733) Stephens, Thomas (1821-1875) Stephens. William (1647 ?-l718) . Stephens, William (1671-1753) Stejiheuson, George(178I-ie48}. Stephenson, Henr^' Pnlfiey (1820-1890) ■StepheoBun, James (1808-1886) Stephenson, Robert (180.1-1859) U) I StepheDson.SBmuel Martin, H.D,(174S- .Stcphcnsan,TbomB« (1552-1634). Stepnev, Clatberine. Ladv (if. 1S4S) Stepney, George (1663-1707). Sterling. See also Stirling. Sterling, Sir ADtbonvG>Diag1iam(1805-187t) 1 Sterling, Edward (1773-1847). See uiuler Sterling, John. Sterling, James ( iJ. I7I8-I7S5). Stertinit.Juhii (1806-1844). Stem, Henrj- Aaron (1820-1885). Sterne or Steanie, John (1624-166!)) Sterne or Steame, John ( 1660-1745) Sterne, Laurenoe (1TI3-176S). Sterne, Richard (1596 ?-16S3). Stembdd, Thomai (d. 1549) . Sterry, Nathaniel (d. 1698). See nnder SleTTV. Peter. Sterrj-, Peter (A 1672) . Stenart. See also Steward, Stewart, and Smart. Steuart, Sir Henry Selon (1759-I8S6) . Steuart or Stewart, Sir James (1635-1715) . Steuart, Sir James, afterward! Deaham (ITI!- ). SeeOeabam. Steuart, formerly Denhim, Sir James (1744- ). See Denbam. Steuart-Seton. Reginald Maodonald (1778- SB1. See nnder Steuart, Sir Henry Setwi. Stevens, Alfred (1818-1875). . ., t. Stevens, Francis f I781-I823) . . , . t- Steruns, George Alexander (1710-1784) . . 2; StevensDrStepliens,John(>J.I726) . .2: Stevrna, Richard John Sunoel ( liG7-IS>7l. tl Steven., William {1783-1807). . . . SI StBTsu, WiUiam Big«hi


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 INDEX TO THE FIFTY-FOURTH VOLUME.


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 cylinder was marked "greatest cold" (0° F.), and from this to the upper end were 24 degrees, some bearing special names; the fourth was "very cold," the eighth "cold," the twelfth "moderate," the sixteenth "warm," the twentieth "very hot," and the twenty-fourth "unbearable heat." The second tube of Wolf differed little in size. Wolf tested the two instruments and found the slight difference between them of one-four hundred and sixteenth of the entire scale.

Another friendly contemporary of Fahrenheit, Dr. Hermann Boerhaave, has recorded in his "Elements of Chemistry" some particulars of the celebrated thermometers. Boerhaave, writing in 1731, ascribes the invention of the thermometer to Drebbel, cites Amontons, Mariotte, and others, and gives an account of a noteworthy experiment made by Fahrenheit, who poured spirit of nitre on ice and got a temperature of −29° F., using an instrument graduated to −79°. Boerhaave then describes "an elegant thermometer made at his request by the skilled artist Daniel Gabriel Fahrenheit" thus: "The lower cylinder of this instrument contains 11,124 parts of mercury, which in the utmost cold observed in Iceland reached to the


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 Fahrenheit made his thermometers with different scales at different times, commonly known as the large, medium, and small scales, their correspondence and value being shown in the table. In No. I the 0° was placed at "temperate" as in the Florentine scale; in No. II each space was divided into four equal parts, and these smaller divisions were afterwards taken as degrees, thus forming scale No. III.

The earliest thermometers were made to indicate temperature up to 96° only; it does not appear that Fahrenheit used the boiling-point of water as a fixed point, although he alludes in his first paper to the fact that Amontons had shown that water boils at a constant temperature. The origin of the numbers 32 for the freezing-point and 212 for the boiling-point of water is obscure, they may have arisen in this way: After Fahrenheit abandoned the Florentine scale −90–0–90, he arbitrarily contrived the scale o–12–24 taken from the familiar foot measure, but the spaces being too


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 large for accurate readings each was divided into four, and thus arose the scale 0–48–96. When he made thermometers for higher temperatures the scale was merely lengthened by adding more spaces of equal size, and one of the divisions marked 212 accidentally coincided with the level of the liquid at the boiling-point of water; Fahrenheit never had any intention of dividing the interval between his zero and the boiling-point of water into 212 parts.

It is a singular thing, however, that if we adopt the fixed points 32 and 212, the actual temperature of the human body is 98° not 96°; so the Fahrenheit scale now in use is not exactly the original. Moreover the zero of the Florentine thermometer is given by him as equal to 45°F. and by others as 48°.

Uncertainty also exists as to the exact temperature selected by Fahrenheit for his zero; the proportions of ice, water, and salt (or sal-ammoniac) in the mixture he used are unknown. Rüdorff has shown that the temperature obtained by mixing 100 parts of snow and 33 of salt equals −21.3° C., and 100 parts snow with 25 of sal-ammoniac gives −15.4° C., whereas the modern Fahrenheit zero is equal to 7.8° C. Fahrenheit's original mixture


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 mark 0 from whence the further degrees of heat are computed upwards. Now if this be immersed in a vessel of water gradually heated, the mercury will be found to ascend continually till the water comes to boil, at 212° or more; so that setting aside the dilatation of the glass it now possesses 11,336 spaces of which in the greatest cold it possessed 11,124, so that by this difference of heat the bulk is dilated to

In another passage, Boerhaave relates that on comparing two of Fahrenheit's thermometers, one of alcohol and one of mercury, he found a slight discrepancy and reported it to the maker, who "ingeniously owned the failing, but did not then see the cause of it, but revolving it in his own mind he at length discovered that the very glass made in Bohemia, England, and Holland expands more or less easily by the same degree of heat," and Fahrenheit suggested that the two instruments ought to be made of one kind of glass. Thereupon the doctor adds this comment: "How circumspect does nature require us to be in order to discover truth in physical matters, and how often are we deceived by following a general rule."