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Rh attracted, as happens for light in the phenomenon of astronomic aberration, so that the effective force is not directed along the straight joining the two bodies, but makes with this straight a small angle. This is a very special hypothesis, not well justified, and, in any case, entirely different from that of Lorentz. Laplace’s result proves nothing against the theory of Lorentz.

Can the preceding theories be reconciled with astronomic observations?

First of all, if we adopt them, the energy of the planetary motions will be constantly dissipated by the effect of the wave of acceleration. From this would result that the mean motions of the stars would constantly accelerate, as if these stars were moving in a resistant medium. But this effect is exceedingly slight, far too much so to be discerned by the most precise observations. The acceleration of the heavenly bodies is relatively slight, so that the effects of the wave of acceleration are negligible and the motion may be regarded as quasi-stationary. It is true that the effects of the wave of acceleration constantly accumulate, but this accumulation itself is so slow that thousands of years of observation would be necessary for it to become sensible. Let us therefore make the calculation considering the motion as quasi-stationary, and that under the three following hypotheses :

A. Admit the hypothesis of Abraham (electrons indeformable) and retain Newton’s law in its usual form;

B. Admit the hypothesis of Lorentz about the deformation of electrons and retain the usual Newton’s law;

C. Admit the hypothesis of Lorentz about electrons and modify Newton’s law as we have done in the preceding paragraph, so as to render it compatible with the principle of relativity.

It is in the motion of Mercury that the effect will be most sensible, since this planet has the greatest velocity. Tisserand formerly made an analogous calculation, admitting Weber’s law; I recall that Weber had sought to explain at the same time the


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516 electrostatic and electrodynamic phenomena in supposing that electrons (whose name was not jet invented) exercise, one upon another, attractions and repulsions directed along the straight joining them, and depending not only upon their distances, but upon the first and second derivatives of these distances, consequently upon their velocities and their accelerations. This law of Weber, different enough from those which to-day tend to prevail, none the less presents a certain analogy with them.

Tisserand found that, if the Newtonian attraction conformed to Weber’s law there resulted, for Mercury’s perihelion, secular variation of 14”, of the same sense as that which has been observed and could not be explained, but smaller, since this is 38”.

Let us recur to the hypotheses A, B and C, and study first the motion of a planet attracted by a fixed center. The hypotheses B and C are no longer distinguished, since, if the attracting point is fixed, the field it produces is a purely electrostatic field, where the attraction varies inversely as the square of the distance, in conformity with Coulomb’s electrostatic law, identical with that of Newton.

The vis viva equation holds good, taking for vis viva the new definition; in the same way, the equation of areas is replaced by another equivalent to it; the moment of the quantity of motion is a constant, but the quantity of motion must be defined as in the new dynamics.

The only sensible effect will be a secular motion of the perihelion. With the theory of Lorentz, we shall find, for this motion, half of what Weber’s law would give; with the theory of Abraham, two fifths.

If now we suppose two moving bodies gravitating around their common center of gravity, the effects are very little different, though the calculations may be a little more complicated. The motion of Mercury’s perihelion would therefore be 7” in the theory of Lorentz and 5”.6 in that of Abraham.

The effect moreover is proportional to n²a², where n is the star’s mean motion and a the radius of its orbit. For the planets, in virtue of Kepler’s law, the effect varies then inversely as $$\sqrt{a^{5}}$$; it is therefore insensible, save for Mercury.

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Rh It is likewise insensible for the moon though n is great, because a is extremely small; in sum, it is five times less for Venus, and six hundred times less for the moon than for Mercury. We may add that as to Venus and the earth, the motion of the perihelion (for the same angular velocity of this motion) would be much more difficult to discern by astronomic observations, because the excentricity of their orbits is much less than for Mercury.

To sum up, the only sensible effect upon astronomic observations would be a motion of Mercury’s perihelion, in the same sense as that which has been observed without being explained, but notably slighter.

That can not be regarded as an argument in favor of the new dynamics, since it will always be necessary to seek another explanation for the greater part of Mercury’s anomaly; but still less can it be regarded as an argument against it.

It is interesting to compare these considerations with a theory long since proposed to explain universal gravitation.

Suppose that, in the interplanetary spaces, circulate in every direction, with high velocities, very tenuous corpuscles. A body isolated in space will not be affected, apparently, by the impacts of these corpuscles, since these impacts are equally distributed in all directions. But if two bodies A and B are present, the body B will play the role of screen and will intercept part of the corpuscles which, without it, would have struck A. Then, the impacts received by A in the direction opposite that from B will no longer have a counterpart, or will now be only partially compensated, and this will push A toward B.

Such is the theory of Lesage; and we shall discuss it, taking first the view-point of ordinary mechanics.

First, how should the impacts postulated by this theory take place; is it according to the laws of perfectly elastic bodies, or according to those of bodies devoid of elasticity, or according to an intermediate law? The corpuscles of Lesage can not act as perfectly elastic bodies; otherwise the effect would be null,


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518 since the corpuscles intercepted by the body B would be replaced by others which would have rebounded from B, and calculation proves that the compensation would be perfect. It is necessary then that the impact make the corpuscles lose energy, and this energy should appear under the form of heat. But how much heat would thus be produced? Note that attraction passes through bodies; it is necessary therefore to represent to ourselves the earth, for example, not as a solid screen, but as formed of a very great number of very small spherical molecules, which play individually the rôle of little screens, but between which the corpuscles of Lesage may freely circulate. So, not only the earth is not a solid screen, but it is not even a cullender, since the voids occupy much more space than the plenums. To realize this, recall that Laplace has demonstrated that attraction, in traversing the earth, is weakened at most by one ten-millionth part, and his proof is perfectly satisfactory: in fact, if attraction were absorbed by the body it traverses, it would no longer be proportional to the masses; it would be relatively weaker for great bodies than for small, since it would have a greater thickness to traverse. The attraction of the sun for the earth would therefore be relatively weaker than that of the sun for the moon, and thence would result, in the motion of the moon, a very sensible inequality. We should therefore conclude, if we adopt the theory of Lesage, that the total surface of the spherical molecules which compose the earth is at most the ten-millionth part of the total surface of the earth.

Darwin has proved that the theory of Lesage only leads exactly to Newton’s law when we postulate particles entirely devoid of elasticity. The attraction exerted by the earth on a mass 1 at a distance 1 will then be proportional, at the same time, to the total surface S of the spherical molecules composing it, to the velocity v of the corpuscles, to the square root of the density ρ of the medium formed by the corpuscles. The heat produced will be proportional to S, to the density ρ, and to the cube of the velocity v.

But it is necessary to take account of the resistance experienced by a body moving in such a medium; it can not move, in fact, without going against certain impacts, in fleeing, on the contrary,


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Rh before those coming in the opposite direction, so that the compensation realized in the state of rest can no longer subsist. The calculated resistance is proportional to S, to ρ and to v; now, we know that the heavenly bodies move as if they experienced no resistance, and the precision of observations permits us to fix a limit to the resistance of the medium.

This resistance varying as Sρv, while the attraction varies as $$S\sqrt{\rho v}$$, we see that the ratio of the resistance to the square of the attraction is inversely as the product Sv.

We have therefore a lower limit of the product Sv. We have already an upper limit of S (by the absorption of attraction by the body it traverses); we have therefore a lower limit of the velocity v, which must be at least 24·1017 times that of light.

From this we are able to deduce ρ and the quantity of heat produced; this quantity would suffice to raise the temperature 1026 degrees a second; the earth would receive in a given time 1020 times more heat than the sun emits in the same time; I am not speaking of the heat the sun sends to the earth, but of that it radiates in all directions.

It is evident the earth could not long stand such a regime.

We should not be led to results less fantastic if, contrary to Darwin’s views, we endowed the corpuscles of Lesage with an elasticity imperfect without being null. In truth, the vis viva of these corpuscles would not be entirely converted into heat, but the attraction produced would likewise be less, so that it would be only the part of this vis viva converted into heat, which would contribute to produce the attraction and that would come to the same thing; a judicious employment of the theorem of the viriel would enable us to account for this.

The theory of Lesage may be transformed; suppress the corpuscles and imagine the ether overrun in all senses by luminous waves coming from all points of space. When a material object receives a luminous wave, this wave exercises upon it a mechanical action due to the Maxwell-Bartholi pressure, just as if it had received the impact of a material projectile. The waves in question could therefore play the role of the corpuscles of Lesage. This is what is supposed, for example, by M. Tommasina.

The difficulties are not removed for all that; the velocity of


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 propagation can be only that of light, and we are thus led, for the resistance of the medium, to an inadmissihle figure. Besides, if the light is all reflected, the effect is null, just as in the hypothesis of the perfectly elastic corpuscles.

That there should be attraction, it is necessary that the light be partially absorbed; but then there is production of heat. The calculations do not differ essentially from those made in the ordinary theory of Lesage, and the result retains the same fantastic character.

On the other hand, attraction is not absorbed by the body it traverses, or hardly at all; it is not so with the light we know. Light which would produce the Newtonian attraction would have to be considerably different from ordinary light and be, for example, of very short wave length. This does not count that, if our eyes were sensible of this light, the whole heavens should appear to us much more brilliant than the sun, so that the son would seem to us to stand out in black, otherwise the sun would repel us instead of attracting us. For all these reasons, light which would permit of the explanation of attraction would be much more like Röntgen rays than like ordinary light.

And besides, the X-rays would not suffice; however penetrating they may seem to us, they could not pass through the whole earth; it would be necessary therefore to imagine X'-rays much more penetrating than the ordinary X-rays. Moreover a part of the energy of these X'-rays would have to be destroyed, otherwise there would be no attraction. If you do not wish it transformed into heat, which would lead to an enormous heat production, you must suppose it radiated in every direction under the form of secondary rays, which might be called X" and which would have to be much more penetrating still than the X'-rays, otherwise they would in their turn derange the phenomena of attraction.

Such are the complicated hypotheses to which we are led when we try to give life to the theory of Lesage.

But all we have said presupposes the ordinary laws of mechanics.

Will things go better if we admit the new dynamics? And first, can we conserve the principles of relativity? Let us give at


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 first to the theory of Lesage its primitive form, and suppose space ploughed by material corpuscles; if these corpuscles were perfectly elastic, the laws of their impact would conform to this principle of relativity, but we know that then their effect would be null. We must therefore suppose these corpuscles are not elastic, and then it is difficult to imagine a law of impact compatible with the principle of relativity. Besides, we should still find a production of considerable heat, and yet a very sensible resistance of the medium.

If we suppress these corpuscles and revert to the hypothesis of the Maxwell-Bartholi pressure, the difficulties will not be less. This is what Lorentz himself has attempted in his Memoir to the Amsterdam Academy of Sciences of April 25, 1900.

Consider a system of electrons immersed in an ether permeated in every sense by luminous waves; one of these electrons, struck by one of these waves, begins to vibrate; its vibration will be synchronous with that of light; but it may have a difference of phase, if the electron absorbs a part of the incident energy. In fact, if it absorbs energy, this is because the vibration of the ether impels the electron; the electron must therefore be slower than the ether. An electron in motion is analogous to a convection current; therefore every magnetic field, in particular that due to the luminous perturbation itself, must exert a mechanical action upon this electron. This action is very slight; moreover, it changes sign in the current of the period; nevertheless, the mean action is not null if there is a difference of phase between the vibrations of the electron and those of the ether. The mean action is proportional to this difference, consequently to the energy absorbed by the electron. I can not here enter into the detail of the calculations; suffice it to say only that the final result is an attraction of any two electrons, varying inversely as the square of the distance and proportional to the energy absorbed by the two electrons.

Therefore there can not be attraction without absorption of light and, consequently, without production of heat, and this it is which determined Lorentz to abandon this theory, which, at bottom, does not differ from that of Lesage-Maxwell-Bartholi. He would have been much more dismayed still if he had pushed


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522 the calculation to the end. He would have found that the temperature of the earth would have to increase 1013 degrees a second.

I have striven to give in few words an idea as complete as possible of these new doctrines; I have sought to explain how they took birth; otherwise the reader would have had ground to be frightened by their boldness. The new theories are not yet demonstrated; far from it; only they rest upon an aggregate of probabilities sufficiently weighty for us not to have the right to treat them with disregard.

New experiments will doubtless teach us what we should finally think of them. The knotty point of the question lies in Kaufmann’s experiment and those that may be undertaken to verify it.

In conclusion, permit me a word of warning. Suppose that, after some years, these theories undergo new tests and triumph; then our secondary education will incur a great danger: certain professors will doubtless wish to make a place for the new theories.

Novelties are so attractive, and it is so hard not to seem highly advanced! At least there will be the wish to open vistas to the pupils and, before teaching them the ordinary mechanics, to let them know it has had its day and was at best good enough for that old dolt Laplace. And then they will not form the habit of the ordinary mechanics.

Is it well to let them know this is only approximative? Yes; but later, when it has penetrated to their very marrow, when they shall have taken the bent of thinking only through it, when there shall no longer be risk of their unlearning it, then one may, without inconvenience, show them its limits.

It is with the ordinary mechanics that they must live; this alone will they ever have to apply. Whatever be the progress of automobilism, our vehicles will never attain speeds where it is not true. The other is only a luxury, and we should think of the luxury only when there is no longer any risk of harming the necessary.


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Rh another to watch over her, one Tom Trebble, a young and handsome moorman, who did not at all relish the manner in which Sir Thomas, Warden of the Stannaries, hovered about Miss Dolly.

But a climax was reached when the Prince Regent arrived at Tor Royal to visit his forest of Dartmoor. The Prince's eye speedily singled Dolly out, and the blue coat and brass buttons, white ducks tightly strapped, and the curled-brimmed hat were to be seen on the way to Dolly's cottage a little too frequently to please Tom Trebble. So to cut his anxieties short he whisked Dolly on to the pillion of his moor cob and rode off with her to Lydford, where they were married. Then he carried her away to this cottage—now a ruin—on the Dart, to which led no road, hardly a path even, and where she was likely to be out of the way of both the Prince and his humble servant, Sir Thomas.

In this solitary cottage Tom and Dolly lived for many years. She survived her husband, and gained her livelihood by working at the tin-mine of Hexworthy, where one of the shafts recently sunk was named after her.

The candle-snuffer realised—so it was said—a good fortune out of the wax taper-ends, and never returned to Dartmoor.

Dolly lived to an advanced age, and even as an old woman was remarkably handsome and of a distinguished appearance.

It is now difficult to collect authentic information concerning her, as only very old people remember Dolly. She was buried at Widdecombe, and aged

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198 moor folk still speak of her funeral, at which all the women mourners wore white skirts, i.e. their white petticoats without the coloured skirts of their gowns, and white kerchiefs pinned as crossovers to cover their shoulders.

The distance is between six and seven miles. Dolly was borne to her grave by the tin-miners, and followed not only by the mine-workers, but by all the women of the moorside, and all in their white petticoats; and as they went they sang psalms.

From Dolly's Cot the hill can be ascended to 'The Seven Sisters," seven conspicuous old Scotch pines, whereof one has lost its head. Thence a road is reached that takes a visitor back to Dartmeet by Brimpts.

The other walk, even finer, is this: Ascend the hill on the Ashburton road till a road breaks away to the left to Sherrill. Follow this, when on the col a kistvaen, inclosed in a circle, is reached. North of this is a much-ruined set of stone rows, three parallel lines running 660 feet, but so plundered that only 158 stones remain. The road descends to a pleasant little settlement, Sherrill, or Sher-well, consisting of a farm and some cottages. The Sher-well bursts out in one strong spring beside the road, and becomes a good stream almost directly.

The situation is warm and sheltered, and the ground is cultivated. The road descends to the Wallabrook, which it crosses, to Babeney. Thence a track leads down the Wallabrook to its junction with the Dart, where is disclosed what I hold to be one

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User:Jack1956

About me
Hi, I'm Jack (not my real name), I am an academic and educationist and I live in the UK near London. My father is Greek Cypriot and my mother is English. My degrees are in Theology (Bachelor of Divinity and Master of Theology) and were awarded by the University of Wales. I am a Fellow]] of the Farmington Institute for Christian Studies, Oxford, a Fellow of the College of Preceptors, a Member of The Ecclesiological Society, the Dickens Fellowship and The British Museum Friends. For 5 years I was Churchwarden of my local church in Baldock and was a ministerial candidate. I was a member of the Society for Psychical Research for ten years, was the founding Chairman of the Crimean War Research Society, a position I held for twelve years, a Friend of the National Army Museum and a member of the Orders and Medals Research Society.

I am married with three children, Alex, Darren and Charlotte, and with a grandson, Miles, born on September 11 2008. Among other things I have an interest in History, Military History, the Victorian era, including the operas of Gilbert and Sullivan, Church History, archaeology and Biblical Archaeology. I have appeared on a couple of UK tv programmes, including Collectors Lot, Going, Going, Gone and Muslim Television Ahmadiyya International.

title: User:Jack1956


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Rh of the finest, if not the finest view on Dartmoor. A tract of level pasture lies at the junction of the streams, and from this Yar Tor soars up a veritable mountain. Few of the Dartmoor heights are so situated as to show themselves to such advantage. On the right, a spur well clothed in dark fir plantations comes down from Brimpts; and on the left is a clitter of bold granite rocks. The time to visit this is certainly the evening, when Yar Tor is bathed in a golden glory, and the woods are steeped in royal purple.

Thence a path, or track rather, leads down the Dart on the east side, past Badgers' Holt to the bridge.

And perhaps on the way the Graphis scripta may be found, but it is chiefly to be discovered on old hollies, a mysterious writing, characters scrawled by delicate hands, and understandable only by the pixies, who are credited with thus writing their messages to one another. Actually this is a lichen, that strangely affects a script.

It was at Badgers' Holt that old Dan Leaman lived, on whom a trick was played which I have already related in my Book of the West.

What a solitary life must have been led by the occupants of the scattered farms and cottages at Babeney, Sherrill, Dury, and the like, in former times! And yet those who occupied them got to love the isolation. A woman at Sherrill, who had been in service and had married a moorman, said to me, "I wouldn't live here if I could help it; but, Lor' bless y', my old man, there's no gettin' he away from atop o' Widdecombe chimney"—that is to say, the level of the

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200 church tower. The reach of its bells formed the world—the only world in which he cared to live. In a cottage near Sherrill lived an old woman absolutely alone, who for sixty years never once allowed her fire to go out.

If it be desired to open out Dartmoor, a road should be carried up the Dart from New Bridge to Dartmeet, and thence, still following the river, to Post Bridge. The owners of the banks of the Dart below New Bridge to Holne Bridge—in fact, of Holne Chase—could then hardly refuse to allow it to be carried through their land to Holne Bridge, and then a drive would be created passing through scenery unsurpassed in England. Another ought to be engineered up the Webburn from its meet with the Dart, past Lizwell to Widdecombe; then that solitary village would be at once accessible, and brought into the world.

Below Dartmeet Bridge, if the river be followed on the right through a wood, the Pixy Holt is reached, a cave in which the little good folk are supposed to dwell. It is the correct thing to leave a pin or some other trifle in acknowledgment when visiting their habitation.

Where the Okebrook drops into the West Dart is an old blowing-house, with moulds for the tin, ruined, and with a stout oak growing up in the midst There are also mortar-stones in the ruin. Above Huccaby Bridge are the remains of a fine circle of standing stones that has been sadly mutilated. Another, far more perfect, is at Sherberton.

Near the bridge is Jolly Lane Cot, the house of

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Rh Sally Satterleigh, that was built and occupied in one day. Her father was desirous of marrying a wife and bringing her to a home; but he had no home to which to introduce her, and the farmers round not only would afford no help, but proved obstructive. One day when it was Holne Revel, and the farmers had gone thither, the labouring people assembled in swarms, set to work and built up the cottage, and before the farmers returned, lively with drink, from the revel, the man was in the cottage and had lighted a fire on the hearth, and this constituted a freeholding from which no man might dispossess him. This man was a notable singer, and his old daughter, now a grandmother, remembered some of his songs. One wild and stormy day, Mr. Bussell, of Brazen Nose College, now Dr. Bussell and tutor of his college, drove over with me from Princetown to get her songs from her.

But old Sally could not sit down and sing. We found that the sole way in which we could extract the ballads from her was by following her about as she did her usual work. Accordingly we went after her when she fed the pigs, or got sticks from the firewood rick, or filled a pail from the spring, pencil and notebook in hand, dotting down words and melody. Finally she did sit to peel some potatoes, when Mr. Bussell with a MS. music-book in hand, seated himself on the copper. This position he maintained as she sang the ballad of "Lord Thomas and the Fair Eleanor," till her daughter applied fire under the cauldron, and Mr. Bussell was forced to skip from his perch.

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202 Holne forms the extreme eastern end of a long ridge that terminates to the west in Down Tor. This hog's back stands over 1,500 feet above the sea, and is the watershed. From it stream the Avon, the Erme, the Yealm, and the Plym in a southerly direction, and north of it are the West Dart and the Swincombe river. It is a rounded back of moor, without granite tors, thickly sown with bogs. But there is a track, the Sandy Way, that threads these morasses from Holne, and leads to Childe's Tomb, a kistvaen, with a cross near it.

The story is well known.

A certain Childe, a hunter, lost his way in winter in this wilderness. Snow fell thick and his horse could go no further.

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Rh The story goes on to say that when the monks of Buckfast heard of this they made ready to transport the body to their monastery. But the monks of Tavistock were beforehand with them; they threw a bridge over the Tavy, ever after called Guile Bridge, and carried the dead Childe to their abbey. Thenceforth they possessed the Plymstock estate.

The kistvaen is, of course, not Childe's grave, for it is prehistoric, and Childe was not buried there. But the cross may have been set up to mark the spot where he was found.

Childe's Cross was quite perfect, standing on a three-stepped pedestal, till in or about 1812, when it was nearly destroyed by the workmen of a Mr. Windeatt, who was building a farmhouse near by. The stones that composed it have, however, been for the most part recovered, and the cross has been restored as well as might be under the circumstances.

The Sandy Way was doubtless a very ancient track across the moor from east to west, as it is marked by crosses, as may be judged by the Ordnance map. 1, Horne's Cross; 2 and 3, crosses on Down Ridge; 4 and 5, crosses on Terhill; 6 and 7, crosses near Fox Tor, in the Newtake; 8,Childe's Cross; 9, Seward's or Nun's Cross; 10, cross on Walkhampton Common.

Swincombe, formerly Swan-combe, runs to the north of the ridge, and has the sources of its river in the Fox Tor mires and near Childe's Tomb.

It runs north-east, and then abruptly passes north to decant into the West Dart.

Near this is Gobbetts Mine, a very interesting

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204 spot, for here are samples of the modern deep mining shaft, the shallow workings, and the deep, open cuttings of the earlier times, and the stream works of the "old men." Thus we have on one spot a compendium of the history of mining for tin. Among the relics lying about are the remains of an old

crazing-mill, consisting of the upper and the nether stones. The nether stone is 3 feet 10 inches in diameter, and 10 inches thick. In the periphery is a groove forming a lip, that served readily to discharge the ground material.

The upper stone has a roughly convex back, and an eye as well as four holes drilled in it. Into these

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Rh holes posts were fitted, which carried two bars, so that the stone was made to revolve by horse or man power, like the arrangement of a capstan.

The hole or eye of the nether stone was for the purpose of receiving a conical plug, the apex of which penetrated partly into the eye of the upper stone, and served the double purpose of keeping the runner stone in position and of distributing the feed equally on the grinding-surfaces. To further assist

this are four curved master-turrows or grooves, radiating from the eye of the grinding-surface of the upper stone. The mill, worked by men or by horses, was of slow speed, and water was introduced to assist the propulsion of the ground material towards the grooved lip in the periphery of the stone. This and the feed were, of course, introduced through the circular hole in the top stone.

On the site of what was evidently the blowing-house is a mould-stone, about 4 feet by 3. The mould is 15 inches long by 11 inches wide at one

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206 end, and 10 inches at the other, and 4 to 5 inches deep. There are also cavities for sample ingots.

Other stones lie about with hollows worked in them, that seem to have been mortar-stones, used for pounding up the ore, at a period earlier than that at which the crazing-mill was introduced.

Further up the Swincombe, on the left, a little stream descends that has had its bed turned over and over. This is Deep Swincombe, and here are the remains of the earliest known smelting-house yet noticed on Dartmoor. It has been fully described in a previous chapter. On all sides we discover traces of those who in ancient times came to Dartmoor and toiled after metal. We go in swarms there now—to spend our metal and idle and gain health. So the old order changeth, and with it men's moods and manners.

To return to Holne. In the parsonage Charles Kingsley was born, but the house has since been to a large extent rebuilt. On a fly-sheet of the Book of Burial Registers is the entry, "The Vicarage House, being very dilapidated, was taken down and rebuilt by the Vicar (the Rev. John D. Parham) in the year 1832." It was in that "very dilapidated" house that Charles Kingsley was born.

A curious custom existed at Holne, now given up. There is, near the village, a "Ploy (play) Field" in which stood formerly a rude granite stone six or seven feet high.

On May morning, before daybreak, the young men of the village were wont to assemble there and then proceed to the moor, where they selected a ram lamb,

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Rh and, after running it down, brought it in triumph to the Ploy Field, fastened it to the granite post, cut its throat, and then roasted it whole—skin, wool, etc. At midday a struggle took place, at the risk of cut hands, for a slice, it being supposed to confer luck for the ensuing year on the fortunate devourer. As an act of gallantry the young men sometimes fought their way through the crowd to get a slice for the chosen amongst the young women, all of whom, in their best dresses, attended the Ram Feast, as it was called. Dancing, wrestling, and other games, assisted by copious libations of cider during the afternoon, prolonged the festivity till midnight. This is now entirely of the past, but a somewhat similar popular festival survives at King's Teignton, or did so till recently. There Whitsuntide is the season chosen. A lamb is drawn about the parish on Whitsun Monday in a cart covered with garlands of lilac, laburnum, and other flowers, when persons are requested to give something towards the animal and attendant expenses. On Tuesday morning it is killed and roasted whole in the middle of the village. The lamb is then sold in slices to the poor at a cheap rate. The story told to account for this festival is that the village once suffered from a dearth of water, when the inhabitants were advised to pray for water; whereupon a fountain burst forth in a meadow about a third of a mile above the river, in an estate now called Rydon, a supply sufficient to meet the necessities of the villagers. A lamb, it is said, has ever since been sacrificed as a return offering at Whitsuntide in the manner above mentioned.

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208 The said water appears like a large pond, from which in rainy weather may be seen jets springing up some inches above the surface in many parts.

I know the case of a farmer on the edge of Dartmoor, whose cattle were afflicted with some disorder in 1879; he thereupon conveyed a sheep to the ridge above his house, sacrificed and burnt it there, as an offering to the Pysgies. The cattle at once began to recover, and did well after, nor were there any fresh cases of sickness amongst them. Since then I have been told of other and very similar cases.

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Advantage of introductory remarks—Natural features of extra-tropical Australia—Difference of temperature between the northern and southern hemispheres—Sterility of the sea-coast—The richest land not preferred, in Australia—The management of water totally neglected—Vulgar error as to the unfitness of Australia for agricultural purposes—Means of water-communication in the new colony—Description of the south coast of Australia—Opinions on that subject.

information obtained upon this subject consists of the evidence of a number of persons who have visited the country. For two reasons, it requires some introductory remarks: first, because it is composed, for the most part, of naked statements of fact, from which no very satisfactory conclusion could be drawn without the aid of some guiding principles in the examination of them; secondly, because in order to prevent the English enquirer from applying some of those facts to wrong conclusions, it is necessary to lay before him other facts which may assist his judgment by means of analogy and comparison. A few mere hints, however, is all that can be offered in this little work.

1. Every known part of extra-tropical Australia presents some features which are peculiar to that part of the world; such as evergreen forests, animals never


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So long as we do not go outside the domain of consciousness, the notion of time is relatively clear. Not only do we distinguish without difficulty present sensation from the remembrance of past sensations or the anticipation of future sensations, but we know perfectly well what we mean when we say that of two conscious phenomena which we remember, one was anterior to the other; or that, of two foreseen conscious phenomena, one will be anterior to the other.

When we say that two conscious facts are simultaneous, we mean that they profoundly interpenetrate, so that analysis can not separate them without mutilating them.

The order in which we arrange conscious phenomena does not admit of any arbitrariness. It is imposed upon us and of it we can change nothing.

I have only a single observation to add. For an aggregate of sensations to have become a remembrance capable of classification in time, it must have ceased to be actual, we must have lost the sense of its infinite complexity, otherwise it would have remained present. It must, so to speak, have crystallized around a center of associations of ideas which will be a sort of label. It is only when they thus have lost all life that we can classify our memories in time as a botanist arranges dried flowers in his herbarium.

But these labels can only be finite in number. On that score, psychologic time should be discontinuous. Whence comes the feeling that between any two instants there are others? We arrange our recollections in time, but we know that there remain empty compartments. How could that be, if time were not a form pre-existent in our minds? How could we know there were empty compartments, if these compartments were revealed to us only by their content?


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224

But that is not all; into this form we wish to put not only the phenomena of our own consciousness, but those of which other consciousnesses are the theater. But more, we wish to put there physical facts, these I know not what with which we people space and which no consciousness sees directly. This is necessary because without it science could not exist. In a word, psychologic time is given to us and must needs create scientific and physical time. There the difficulty begins, or rather the difficulties, for there are two.

Think of two consciousnesses, which are like two worlds impenetrable one to the other. By what right do we strive to put them into the same mold, to measure them by the same standard? Is it not as if one strove to measure length with a gram or weight with a meter? And besides, why do we speak of measuring? We know perhaps that some fact is anterior to some other, but not by how much it is anterior.

Therefore two difficulties: (1) Can we transform psychologic time, which is qualitative, into a quantitative time? (2) Can we reduce to one and the same measure facts which transpire in different worlds?

The first difficulty has long been noticed; it has been the subject of long discussions and one may say the question is settled. We have not a direct intuition of the equality of two intervals of time. The persons who believe they possess this intuition are dupes of an illusion. When I say, from noon to one the same time passes as from two to three, what meaning has this affirmation?

The least reflection shows that by itself it has none at all. It will only have that which I choose to give it, by a definition which will certainly possess a certain degree of arbitrariness. Psychologists could have done without this definition; physicists and astronomers could not; let us see how they have managed.

To measure time they use the pendulum and they suppose by definition that all the beats of this pendulum are of equal duration. But this is only a first approximation; the temperature, the resistance of the air, the barometric pressure, make the pace


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Rh of the pendulum vary. If we could escape these sources of error, we should obtain a much closer approximation, but it would still be only an approximation. New causes, hitherto neglected, electric, magnetic or others, would introduce minute perturbations.

In fact, the best chronometers must be corrected from time to time, and the corrections are made by the aid of astronomic observations; arrangements are made so that the sidereal clock marks the same hour when the same star passes the meridian. In other words, it is the sidereal day, that is, the duration of the rotation of the earth, which is the constant unit of time. It is supposed, by a new definition substituted for that based on the beats of the pendulum, that two complete rotations of the earth about its axis have the same duration.

However, the astronomers are still not content with this definition. Many of them think that the tides act as a check on our globe, and that the rotation of the earth is becoming slower and slower. Thus would be explained the apparent acceleration of the motion of the moon, which would seem to be going more rapidly than theory permits because our watch, which is the earth, is going slow.

All this is unimportant, one will say; doubtless our instruments of measurement are imperfect, but it suffices that we can conceive a perfect instrument. This ideal can not be reached, but it is enough to have conceived it and so to have put rigor into the definition of the unit of time.

The trouble is that there is no rigor in the definition. When we use the pendulum to measure time, what postulate do we implicitly admit? It is that the duration of two identical phenomena is the same; or, if you prefer, that the same causes take the same time to produce the same effects.

And at first blush, this is a good definition of the equality of two durations. But take care. Is it impossible that experiment may some day contradict our postulate?

Let me explain myself. I suppose that at a certain place in the world the phenomenon $$\alpha$$ happens, causing as consequence at the end of a certain time the effect $$\alpha'$$. At another place in the world


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226 very far away from the first, happens the phenomenon $$\beta$$, which causes as consequence the effect $$\beta'$$. The phenomena $$\alpha$$ and $$\beta$$ are simultaneous, as are also the effects $$\alpha'$$ and $$\beta'$$.

Later, the phenomenon $$\alpha$$ is reproduced under approximately the same conditions as before, and simultaneously the phenomenon $$\beta$$ is also reproduced at a very distant place in the world and almost under the same circumstances. The effects $$\alpha'$$ and $$\beta'$$ also take place. Let us suppose that the effect $$\alpha'$$ happens perceptibly before the effect $$\beta'$$.

If experience made us witness such a sight, our postulate would be contradicted. For experience would tell us that the first duration $$\alpha\alpha'$$ is equal to the first duration $$\beta\beta'$$ and that the second duration $$\alpha\alpha'$$ is less than the second duration $$\beta\beta'$$. On the other hand, our postulate would require that the two durations $$\alpha\alpha'$$ should be equal to each other, as likewise the two durations $$\beta\beta'$$. The equality and the inequality deduced from experience would be incompatible with the two equalities deduced from the postulate.

Now can we affirm that the hypotheses I have just made are absurd? They are in no wise contrary to the principle of contradiction. Doubtless they could not happen without the principle of sufficient reason seeming violated. But to justify a definition so fundamental I should prefer some other guarantee.

But that is not all. In physical reality one cause does not produce a given effect, but a multitude of distinct causes contribute to produce it, without our having any means of discriminating the part of each of them.

Physicists seek to make this distinction; but they make it only approximately, and, however they progress, they never will make it except approximately. It is approximately true that the motion of the pendulum is due solely to the earth’s attraction; but in all rigor every attraction, even of Sirius, acts on the pendulum.

Under these conditions, it is clear that the causes which have produced a certain effect will never be reproduced except approximately. Then we should modify our postulate and our


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Rh definition. Instead of saying: ‘The same causes take the same time to produce the same effects,’ we should say: ‘Causes almost identical take almost the same time to produce almost the same effects.’

Our definition therefore is no longer anything but approximate. Besides, as M. Calinon very justly remarks in a recent memoir:

One of the circumstances of any phenomenon is the velocity of the earth’s rotation; if this velocity of rotation varies, it constitutes in the reproduction of this phenomenon a circumstance which no longer remains the same. But to suppose this velocity of rotation constant is to suppose that we know how to measure time.

Our definition is therefore not yet satisfactory; it is certainly not that which the astronomers of whom I spoke above implicitly adopt, when they affirm that the terrestrial rotation is slowing down.

What meaning according to them has this affirmation? We can only understand it by analyzing the proofs they give of their proposition. They say first that the friction of the tides producing heat must destroy vis viva. They invoke therefore the principle of vis viva, or of the conservation of energy.

They say next that the secular acceleration of the moon, calculated according to Newton’s law, would be less than that deduced from observations unless the correction relative to the slowing down of the terrestrial rotation were made. They invoke therefore Newton’s law. In other words, they define duration in the following way: time should be so defined that Newton’s law and that of vis viva may be verified. Newton’s law is an experimental truth; as such it is only approximate, which shows that we still have only a definition by approximation.

If now it be supposed that another way of measuring time is adopted, the experiments on which Newton’s law is founded would none the less have the same meaning. Only the enunciation of the law would be different, because it would be translated into another language; it would evidently be much less simple. So that the definition implicitly adopted by the astronomers may be summed up thus: Time should be so defined that


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228 the equations of mechanics may be as simple as possible. In other words, there is not one way of measuring time more true than another; that which is generally adopted is only more convenient. Of two watches, we have no right to say that the one goes true, the other wrong; we can only say that it is advantageous to conform to the indications of the first.

The difficulty which has just occupied us has been, as I have said, often pointed out; among the most recent works in which it is considered, I may mention, besides M. Calinon’s little book, the treatise on mechanics of Andrade.

The second difficulty has up to the present attracted much less attention; yet it is altogether analogous to the preceding; and even, logically, I should have spoken of it first.

Two psychological phenomena happen in two different consciousnesses; when I say they are simultaneous, what do I mean? When I say that a physical phenomenon, which happens outside of every consciousness, is before or after a psychological phenomenon, what do I mean?

In 1572, Tycho Brahe noticed in the heavens a new star. An immense conflagration had happened in some far distant heavenly body; but it had happened long before; at least two hundred years were necessary for the light from that star to reach our earth. This conflagration therefore happened before the discovery of America. Well, when I say that; when, considering this gigantic phenomenon, which perhaps had no witness, since the satellites of that star were perhaps uninhabited, I say this phenomenon is anterior to the formation of the visual image of the isle of Española in the consciousness of Christopher Columbus, what do I mean?

A little reflection is sufficient to understand that all these affirmations have by themselves no meaning. They can have one only as the outcome of a convention.

We should first ask ourselves how one could have had the idea of putting into the same frame so many worlds impenetrable to


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Rh one another. We should like to represent to ourselves the external universe, and only by so doing could we feel that we understood it. We know we never can attain this representation: our weakness is too great. But at least we desire the ability to conceive an infinite intelligence for which this representation could be possible, a sort of great consciousness which should see all, and which should classify all in its time, as we classify, in our time, the little we see.

This hypothesis is indeed crude and incomplete, because this supreme intelligence would be only a demigod; infinite in one sense, it would be limited in another, since it would have only an imperfect recollection of the past; and it could have no other, since otherwise all recollections would be equally present to it and for it there would be no time. And yet when we speak of time, for all which happens outside of us, do we not unconsciously adopt this hypothesis; do we not put ourselves in the place of this imperfect god; and do not even the atheists put themselves in the place where god would be if he existed?

What I have just said shows us, perhaps, why we have tried to put all physical phenomena into the same frame. But that can not pass for a definition of simultaneity, since this hypothetical intelligence, even if it existed, would be for us impenetrable. It is therefore necessary to seek something else.

The ordinary definitions which are proper for psychologic time would suffice us no more. Two simultaneous psychologic facts are so closely bound together that analysis can not separate without mutilating them. Is it the same with two physical facts? Is not my present nearer my past of yesterday than the present of Sirius?

It has also been said that two facts should be regarded as simultaneous when the order of their succession may be inverted at will. It is evident that this definition would not suit two physical facts which happen far from one another, and that, in what concerns them, we no longer even understand what this reversibility would be; besides, succession itself must first be defined.


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230

Let us then seek to give an account of what is understood by simultaneity or antecedence, and for this let us analyze some examples.

I write a letter; it is afterward read by the friend to whom I have addressed it. There are two facts which have had for their theater two different consciousnesses. In writing this letter I have had the visual image of it, and my friend has had in his turn this same visual image in reading the letter. Though these two facts happen in impenetrable worlds, I do not hesitate to regard the first as anterior to the second, because I believe it is its cause.

I hear thunder, and I conclude there has been an electric discharge; I do not hesitate to consider the physical phenomenon as anterior to the auditory image perceived in my consciousness, because I believe it is its cause.

Behold then the rule we follow, and the only one we can follow: when a phenomenon appears to us as the cause of another, we regard it as anterior. It is therefore by cause that we define time; but most often, when two facts appear to us bound by a constant relation, how do we recognize which is the cause and which the effect? We assume that the anterior fact, the antecedent, is the cause of the other, of the consequent. It is then by time that we define cause. How save ourselves from this petitio principii?

We say now post hoc, ergo propter hoc; now propter hoc, ergo post hoc; shall we escape from this vicious circle?

Let us see, not how we succeed in escaping, for we do not completely succeed, but how we try to escape.

I execute a voluntary act $$A$$ and I feel afterward a sensation $$D$$, which I regard as a consequence of the act $$A$$; on the other hand, for whatever reason, I infer that this consequence is not immediate, but that outside my consciousness two facts $$B$$ and $$C$$, which I have not witnessed, have happened, and in such a way that $$B$$ is the effect of $$A$$, that $$C$$ is the effect of $$B$$, and $$D$$ of $$C$$.

But why? If I think I have reason to regard the four facts $$A, B, C, D,$$ as bound to one another by a causal connection, why


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10 seen elsewhere, and the total want of animals which are numerous in other countries. But the most striking, perhaps, of Australian peculiarities is the sameness of those natural features on every part, that has yet been visited, of a line of coast some thousand miles in extent. In North America, and still more in Europe, a difference of latitude, or even of longitude, is generally attended with remarkable differences of soil, climate, and natural productions: whereas throughout Australia, south of the tropic, the climate, allowing for differences of mere temperature in different latitudes, appears to be every where the same; and the soil presents every where the same peculiar features, supporting every where the same peculiar vegetation and the same peculiar animals; from Moreton Bay near the tropic on the East, through Port Jackson, Port Philip, the Tamar, Nepean Bay, Port Lincoln, King George's Sound, and the Swan River, to Shark's Bay near the tropic on the West. From the extent to which this peculiarity of sameness is known, we may infer that it will be more fully established.

In other words, from the perfect sameness of all the known parts of this vast region, we may conclude that such sameness extends to the parts which are still unknown. The discovery of a part of the coast differing materially in its natural circumstances from the other parts, would astonish those who are acquainted with all that is known at present. Such persons will take for granted that South Australia enjoys the great natural fertilizing power which arises from rainy and dry seasons, because they know that New South Wales does. Without multiplying such examples it will be seen, that in forming conjectural


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Rh range them in the causal order $$A B C D$$, and at the same time in the chronologic order $$A B C D$$, rather than in any other order?

I clearly see that in the act $$A$$ I have the feeling of having been active, while in undergoing the sensation $$D$$ I have that of having been passive. This is why I regard $$A$$ as the initial cause and $$D$$ as the ultimate effect; this is why I put $$A$$ at the beginning of the chain and $$D$$ at the end; but why put $$B$$ before $$C$$ rather than $$C$$ before $$B$$?

If this question is put, the reply ordinarily is: we know that it is $$B$$ which is the cause of $$C$$ because we always see $$B$$ happen before $$C$$. These two phenomena, when witnessed, happen in a certain order; when analogous phenomena happen without witness, there is no reason to invert this order.

Doubtless, but take care; we never know directly the physical phenomena $$B$$ and $$C$$. What we know are sensations $$B'$$ and $$C'$$ produced respectively by $$B$$ and $$C$$. Our consciousness tells us immediately that $$B'$$ precedes $$C'$$ and we suppose that $$B$$ and $$C$$ succeed one another in the same order.

This rule appears in fact very natural, and yet we are often led to depart from it. We hear the sound of the thunder only some seconds after the electric discharge of the cloud. Of two flashes of lightning, the one distant, the other near, can not the first be anterior to the second, even though the sound of the second comes to us before that of the first?

Another difficulty; have we really the right to speak of the cause of a phenomenon? If all the parts of the universe are interchained in a certain measure, any one phenomenon will not be the effect of a single cause, but the resultant of causes infinitely numerous; it is, one often says, the consequence of the state of the universe a moment before. How enunciate rules applicable to circumstances so complex? And yet it is only thus that these rules can be general and rigorous.

Not to lose ourselves in this infinite complexity, let us make a simpler hypothesis. Consider three stars, for example, the sun, Jupiter and Saturn; but, for greater simplicity, regard them as


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232 reduced to material points and isolated from the rest of the world. The positions and the velocities of three bodies at a given instant suffice to determine their positions and velocities at the following instant, and consequently at any instant. Their positions at the instant $$t$$ determine their positions at the instant $$t+h$$ as well as their positions at the instant $$t-h$$.

Even more; the position of Jupiter at the instant $$t$$, together with that of Saturn at the instant $$t+a$$, determines the position of Jupiter at any instant and that of Saturn at any instant

The aggregate of positions occupied by Jupiter at the instant $$t + e$$ and Saturn at the instant $$t+a+e$$ is bound to the aggregate of positions occupied by Jupiter at the instant $$t$$ and Saturn at the instant $$t+a$$, by laws as precise as that of Newton, though more complicated. Then why not regard one of these aggregates as the cause of the other, which would lead to considering as simultaneous the instant $$t$$ of Jupiter and the instant $$t+a$$ of Saturn?

In answer there can only be reasons, very strong, it is true, of convenience and simplicity.

But let us pass to examples less artificial; to understand the definition implicitly supposed by the savants, let us watch them at work and look for the rules by which they investigate simultaneity.

I will take two simple examples, the measurement of the velocity of light and the determination of longitude.

When an astronomer tells me that some stellar phenomenon, which his telescope reveals to him at this moment, happened, nevertheless, fifty years ago, I seek his meaning, and to that end I shall ask him first how he knows it, that is, how he has measured the velocity of light.

He has begun by supposing that light has a constant velocity, and in particular that its velocity is the same in all directions. That is a postulate without which no measurement of this velocity could be attempted. This postulate could never be verified directly by experiment; it might be contradicted by it if the results of different measurements were not concordant. We


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Rh should think ourselves fortunate that this contradiction has not happened and that the slight discordances which may happen can be readily explained.

The postulate, at all events, resembling the principle of sufficient reason, has been accepted by everybody; what I wish to emphasize is that it furnishes us with a new rule for the investigation of simultaneity, entirely different from that which we have enunciated above.

This postulate assumed, let us see how the velocity of light has been measured. You know that Roemer used eclipses of the satellites of Jupiter, and sought how much the event fell behind its prediction. But how is this prediction made? It is by the aid of astronomic laws; for instance Newton’s law.

Could not the observed facts be just as well explained if we attributed to the velocity of light a little different value from that adopted, and supposed Newton’s law only approximate? Only this would lead to replacing Newton’s law by another more complicated. So for the velocity of light a value is adopted, such that the astronomic laws compatible with this value may be as simple as possible. When navigators or geographers determine a longitude, they have to solve just the problem we are discussing; they must, without being at Paris, calculate Paris time. How do they accomplish it? They carry a chronometer set for Paris. The qualitative problem of simultaneity is made to depend upon the quantitative problem of the measurement of time. I need not take up the difficulties relative to this latter problem, since above I have emphasized them at length.

Or else they observe an astronomic phenomenon, such as an eclipse of the moon, and they suppose that this phenomenon is perceived simultaneously from all points of the earth. That is not altogether true, since the propagation of light is not instantaneous; if absolute exactitude were desired, there would be a correction to make according to a complicated rule.

Or else finally they use the telegraph. It is clear first that the reception of the signal at Berlin, for instance, is after the sending of this same signal from Paris. This is the rule of cause and effect analyzed above. But how much after? In general, the duration of the transmission is neglected and the two events are


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234 regarded as simultaneous. But, to be rigorous, a little correction would still have to be made by a complicated calculation; in practise it is not made, because it would be well within the errors of observation; its theoretic necessity is none the less from our point of view, which is that of a rigorous definition. From this discussion, I wish to emphasize two things: (1) The rules applied are exceedingly various. (2) It is difficult to separate the qualitative problem of simultaneity from the quantitative problem of the measurement of time; no matter whether a chronometer is used, or whether account must be taken of a velocity of transmission, as that of light, because such a velocity could not be measured without measuring a time.

To conclude: We have not a direct intuition of simultaneity, nor of the equality of two durations. If we think we have this intuition, this is an illusion. We replace it by the aid of certain rules which we apply almost always without taking count of them.

But what is the nature of these rules? No general rule, no rigorous rule; a multitude of little rules applicable to each particular case.

These rules are not imposed upon us and we might amuse ourselves in inventing others; but they could not be cast aside without greatly complicating the enunciation of the laws of physics, mechanics and astronomy.

We therefore choose these rules, not because they are true, but because they are the most convenient, and we may recapitulate them as follows: “The simultaneity of two events, or the order of their succession, the equality of two durations, are to be so defined that the enunciation of the natural laws may be as simple as possible. In other words, all these rules, all these definitions are only the fruit of an unconscious opportunism.”


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Rh opinions concerning natural circumstances, this is the country, beyond all others, in which we may trust to the guide of analogy. Amongst the most useful means of forming a correct judgment as to South Australia, are the published accounts of New South Wales and Van Diemen's Land; and indeed it may be said that he who is not familiarly acquainted with the general features of Australia, is hardly qualified to form a confident opinion, one way or the other, as to the natural circumstances of the southern coast.

2. In the southern hemisphere, owing to the large proportion which sea bears to land, the temperature does not agree with that of corresponding latitudes in the northern hemisphere, but is generally found to be cooler by two or three degrees. Thus the temperature of Port Lincoln in 35°, South, may be expected to agree with that of places on the sea-coast between 37° and 38° of North latitude.

3. Except where the land is gaining on the sea by the deposits of great rivers, land close to the sea is generally less fertile than land some way removed from it. This is peculiarly the case in every known part of extra-tropical Australia. Here, it seems, the sea is almost universally separated from land of superior fertility by a stripe of very poor land, commonly of sand, bearing only stunted brushwood, and varying in breadth from two or three, to twenty or thirty miles.

Very fine land close to the sea, where the sea is not touched by a range of high land, is a rare exception to the general rule of sameness already noticed.

Hence we are never to presume from the known