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A terrible light burst upon Shafto. He looking up at him, said falteringly, "I am felt as if a cold hand seized his heart and so sorry. I beg your pardon.". with a mortal faintness coming over him, and great drops standing icily on his forehead, he withdrew a step or two, and leaned heavily on the back of Nelly's chair.

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No, Nelly was not undemonstrative, when she had anything to demonstrate, as she never had had, never would have, now for him. And yet, yet - but for this bitter chance, this lightning flash which bared the desolate path of duty so plain before him, she might have been his and have learned, by degrees, to be comforted, and forget the other.

These waters of Marah almost choked his speech but he drove them back manfully, and answered with simple conscientiousness, "Yes, I knew him a little. He was not married, nor a bit likely to be. He was not quite well when I last saw him, but he was getting better. I was with him the night before I left-I little thought

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His voice failed him suddenly, he went away from her, and stood leaning his hands on the stone balustrade, with his face turned up to the night sky. There were no tears in his eyes to dim the radiance of the starlight, nor any passionate outcries on his lips. And as to what was in his heart then, that was between himself and God, for no one else ever knew it. He came back presently; Nelly, who had been reproaching herself for her selfish outburst, put her hand in his, and

Those eyes, that voice, so full of his rival, with only pity to spare for him, made him hard for a moment, but the next he rebuked himself sternly, and answered with a kind sad smile,

“No, my darling, I beg yours for leaving you when you were so ill; but - but I've got rather a headache," added he, piteously, trying to excuse his shaken voice, "I'm knocked up with the journey, I think."

"Poor Shafto!" said she compassionately, putting her hand on his head, which he had bent down to her; but he drew back sharply, with an inarticulate sound of pain, and suggested, if she was better, they should go back to the drawing-room. He took her to her seat, and then, going up to a group of men gathered round some Indian photographs he had brought home, asked, "Can any one tell me when the Calcutta mail goes out? Is this week's gone ?"

"Doesn't go till Friday. But I say, Elphinstone," added the speaker, staring at him, "What on earth is the matter? You look as if you had seen a ghost."

"I'm all right. At least, I've a headache, that's all," he answered, wearily. "Perhaps Miss Western

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"Let Miss Western alone, and me too," said Shafto with sudden sternness, turning on his heels, and going off.

"Nelly," said Mrs. Wroughton, later in the evening, "What have you been doing to your victim? He looks so pale, and heavy-eyed, and the picture of misery. What a tyrant you must be!"

Nelly explained wearily how the song had affected her, and Shafto had guessed the cause.

"A nice little incident for him to dream upon," remarked her friend drily; I wonder how many men would stand such a thing. A brilliant, uncomfortable, unsatisfactory creature like your Dennis, for instance!"

"That he isn't my Dennis now should prevent your blaming him," returned Nelly calmly, but with very white lips.

Elphinstone's "good-night" was tranquil as usual; but after he had said it, and let go her hand, he took it again, and added unreasonably, "O Nelly!" much as she had said, an hour before. "O Dennis!" and looked at her with quite a new profundity of expression.

He was a passive and abstracted host in the smoking-room that night, and when he went to his own apartment, took pen and

paper with an air of melancholy resolu- | write, if you can accept my offer, but come tion. home immediately.

"SHAFTO ELPHINSTONE."

But he could not write - not at once, "This matter, as you will understand, must with all that tumult within him, with be between ourselves whatever the result. I that great bitter rebellious wonder at the hope you have quite recovered from your illness uselessness of his love gnawing at his by this time. Believe me, yours truly, heart. "I was so happy before," he thought. I didn't try to love her, and I do love her so." He leaned his hot head on his hands, and looked over the gardens and woods and fields, bathed in starlight, with sore regret. Their pleasure was spoiled to him, most likely forever, as, indeed, the pleasure of every thing was.

"I suppose I was too happy," said Shafto, mournfully.

"But I did believe I could make her happy too. Well, I may do that yet, thank God! in another way. And - poor Kilcourcy as well."

It was a little struggle to speak thus kindly of his rival, his conqueror, but somehow the recollection of Dennis's faint hand and fevered eyes made it easier.

"Yes," added he, after some serious reflection, "I'll write to him at once. But I'll be the same to her, and say nothing till I hear from him, or he comes; because if he should have changed, she would be as forlorn, and want me to comfort her as much as ever, poor little girl! Not that he will be changed! How could

he be!"

So Shafto sat down, and wrote many letters, and flung them aside, and it was not till the morning light reddened the window panes, and dazzled his tired eyes, and the birds sang their matins outside, that he had produced a satisfactory epistle. He had little gift of composition, and feeling how much of his darling's happiness hung on this issue, trembled lest his own want of tact should ruin all.

He despatched this missive of doom by a groom, and having renewed his toi lette, went down to breakfast.

From The Gentleman's Magazine THE POSSIBILITIES OF A COMETARY COLLISION.

A FEW weeks ago nervous Britain was thrown into a state of wild excitement, by the announcement that a comet was on its way towards our system, and would encounter the earth full tilt on the 12th of the coming August. The statement came from sober Switzerland; it was reported to have been made upon the authority of an astronomer of high repute; there was in it some slight internal evidence of circumstantiality - enough to commend it to those not deeply versed in astronomic lore; and so, with that faith in astronomical predictions which the general accuracy of such forecasts has inspired, the public, or a very large section of it, accepted the warning as reliable in so far as the actual encounter was concerned, and set itself wondering what might be the possible consequences of the threatened collision. According to their lights folks were reassured or doubted, or were alarmed, or were indifferent. Those who had learnt to regard comets as airy nothings treated the report with contempt; those who retained the ancient and classical dread of a bearded star were dispirited, and in some cases ad"DEAR KILCOURCY, - You will be surprised dressed themselves to astronomical authorto hear from me; but you will soon understand ities in the hope of receiving information the reason. You remember the story you told ex cathedra to allay their fears. They were me that night I have met the young lady you not disappointed; the authorities were enspoke of, and in my opinion she has not forgot-abled to contradict the alarming report on ten you. If you love her the same as ever- all its essential points, and to offer a feasiand I would not write this if I did not believe ble suggestion as to the harmless circumit - come home. With regard to money mat-stances out of which, by enormous exagters, it happens that I am now in search of some geration, it had been concocted. The reagentleman to live at my place in Sussex, air the sonable explanation was that the canard house, and look after the farm and shooting. had been generated from the facts that the The man who is there at present, Major Anson, earth encounters a meteor stream on or who receives five hundred a year from me, has about the date referred to, and that metecome into money and a house of his own. you will not mind taking such a thing, which ors are in some manner allied to comets, perhaps you will not for another person's sake, perhaps very intimately, inasmuch as cerI think you would like the neighbourhood tain meteor streams have been discovered there is good hunting and shooting, and I know to occupy and course around the orbits of Miss Western thinks it pretty. Do not wait to certain comets; and it has even been sur

If

curred but a few years ago. The great comet of 1861 is fully believed to have dragged his tail over us on Sunday, the 30th of June in that year, when we were only two-thirds the tail's length from the nucleus. This fact was first deduced by calculation, and it has received curious con

mised that what is solid in a comet is mere-] or supposed solid part; the nebulous surly a swarm of meteoric particles. In the rounding which commonly streams off to actual case in question it is known that a form the customary tail might have a vastcomet which itself passed in sight of us in ly greater size, and the probabilities of the year 1862 has its path strewed with encountering it would be correspondingly meteoric particles, as with debris that it has increased. But we may dismiss at once left behind it. The earth intersects this any apprehensions of danger from a swish path every 11th of August, and some of of a comet's caudal appendage, for there these particles then plunge into our atmos- is little doubt that we have repeatedly rephere, and are kindled into visibility, giv-ceived this, the latest instance having ocing rise to the luminous meteors of that date, which have long been known in tradition-loving Ireland as St. Lawrence's fiery tears. So that on that critical date we do encounter the trail (not the tail, for comets do not trail their tails) of a comet - with what harmless consequences we all know and it is conceivable that the re-firmation from observations that have subport to which we have alluded grew out of some simple announcement of this circumstance. It may be suspected that since each year we cross the comet's path we may one day fall foul of the body itself: so we may, but it will not be this year, nor in the life-time of any one who now reads these remarks, for the last approach was in the year 1862, and, since the comet's period of revolution round its vast orbit is 113 years, it will not come near us again till the year 1975, and the odds against the probability of an encounter even then are

enormous.

We have, therefore, little to fear from that comet, though we do actually run across the path it traverses. But Kepler declared that space was as full of comets as the sea is of fishes; and, considering the infinity of space, his metaphor may not be so far overdrawn as, apart from this consideration, we might be disposed to regard it. Arago, indeed, endorsed the Keplerian assertion so far as to estimate that the number of cometary bodies which in their orbital journeys pass through the solar system amounts to over seventeen millions. Clearly this plenitude must induce some risk of an earth-and-comet collision, for we know of no provision of nature for warding off such an encounter, though we may suppose provisions to exist for rendering it innocuous if by any chance it should occur. But the chances of occurrence are feeble indeed. The illustrious French astronomer whose name we have just mentioned calculated the probabilities of an encounter for a hypothetical comet a quarter the diameter of the earth in size, and supposed to approach the sun within the earth's orbit: and he found that the odds against the meeting were 281 millions to one. The assumed small diameter of the comet referred of course to the nucleus,

sequently come to hand; for an Australian observer, viewing the comet at a time corresponding to our afternoon (when it was night with him), saw the branches or sideboundaries of the tail widen out; and on the same evening, a few hours later, two English observers saw the closing-up or the narrowing of the tail-cone; these effects being those which considerations of perspective would lead us to refer to an approach to us and a recedence from us. It is reasonable to conclude that the whole earth actually passed through, and was for a time enveloped by, the tail at about sunset on the day in question. We are not aware that any consequences injurious to man or appreciable by him followed from the encounter; we had not even a trace of anything similar to the dry fogs of 1783 and 1831, which were at one time regarded as due to cometary exhalations gathered in some such conflict as that here alluded to.

Arago was not the only astronomer who had the curiosity to compute the probabilities or the improbabilities of a cometary collision. Olbers made a somewhat similar calculation, taking for granted that every year two comets come within the sphere which coalesces with the earth's orbit, and assuming the comets to have an average diameter of one-fifth that of the earth; and he arrived at the conclusion that our globe would collide with one such wanderer once in the course of 219 millions of years. He went so far as to point out that the most likely comet to run into us was the famous little one known as Encke's, which visits our skies every threeand-a-quarter years, and list paid its respects to us six months ago.

Small as is the chance of a collision, it nevertheless exists; and in the face of the possibility speculative philosophers have not hesitated to credit a comet with caus

ing some of the convulsions that have in As we are dealing rather with what is curemote ages so distorted and overturned rious than what is important, we remark the surface of the earth. "When we con- by the way that Lalande's memoir emtemplate," said a prize essayist* on com- bodying his calculations created a furore ets, writing in 1828, "the broken and lac- in France in 1773, the year of its producerated appearance which the map of the tion. It was to have been read to the world exhibits; when we consider the Academy of Sciences. It was not read; irregularity and confusion characterizing but its purport was bruited the next day, the constitution of its crust; when we re- and of course misunderstood. Lalande flect upon the discovery of numerous was declared to have announced a comet plants and animals, in every different cli- that was to destroy the world in a year, a mate and situation, buried under the sur-month, ay, in a week. Such a panic was face; we can hardly entertain a doubt raised that the police authorities had to that tremendous convulsions have taken demand of the astronomer a prompt and place upon the earth, attributable to sud- reassuring explanation. This was at once den inundations from the ocean; and that given and published in the Gazette de event, of whose occurrence, geography, France; but it was of small avail; he was geology, and natural history combine to inundated with letters and anxious infurnish evidence, the universal tradition quiries, and he determined upon giving of every people, however barbarous, seems full publicity to his calculations; whether to confirm. It has been supposed that the these sufficed to allay the public fears the deluges which are said to have taken place historian does not inform us. at different periods in the history of the From the foregoing statements it will world may have been occasioned by the have been gleaned that a surpassingly collision of comets; and it cannot be de- high tide is one of the conceivable consenied that, on reflecting with attention quences, not of an actual collision with, upon the various circumstances by which but of mere approach to a comet. Olbers those deluges are still recorded, the sup- calculated what would be the tidal effect position does not seem destitute of founda- of the forementioned comet of Encke if it tion." They who resorted to this suppo- should approach- as some day it may, sition did so because they failed to dis- supposing it does not suffer dissipation, as cover in the earth itself any disturbing returning comets hitherto appear to have cause of sufficient power to produce the done as near to us as the moon. And enormous changes that have been brought it was found that if its attraction should about notably those by which the ocean equal that of the earth the waters of the was caused to cover and leave its remains ocean would be elevated 13,000 feet, overupon high lands and mountains. They topping every European mountain except argued that a deluge might be produced Mont Blanc, and leaving only the inhabiteither by the actual collision or by the ants of the Andes and the Himalayas to near approach of the comet; the writer repeople the globe. This seems very terjust quoted favoured the former hypothe-rible; happily the fearful result is derived sis, believing that the latter was insuffi- from data containing one unjustifiable ascient to account for the manifested effects. sumption, that which we have italicized in The famous Lalande, however, had preIn this case, as in viously shown that if a comet as heavy as others we have cited, the mass of the bythe earth were to come within six times pothetically colliding or endangering comet the distance of the moon, it would exert has been fixed far beyond the probable such a powerful attraction upon the waters limits. By mass we do not mean bulk, of our globe as to pull up a tidal wave but weight or attractive power. There "2,000 toises above the ordinary sea level, are no grounds for assuming an ordinary and thus inundate all the continents of the comet's mass to be at all comparable to world." In this calculation it was sup- that of the earth. We are not aware that posed that the comet might remain long any actual determination of this datum enough over one region of the earth to has ever been made, but it has been proved overcome the inertia of the waters, a con- that the quantity must be insignificantly dition which another calculator, Du Se- small. This we know from the oft-cited jour, showed to be almost impossible. case of the comet of 1770, known as 'Lexell's which twice went right into Jupiter's system, actually getting entangled, so to speak, among his four moons. Now these moons, though they range from 2,000 to 3,400 miles in diameter, have very small

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David Milne, A.M., F.R.S.E., afterwards David Milne-Home, author of numerous memoirs on earthquakes and other geological perturbations; and of late Vice-President of the Royal Society of Edinburgh.

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masses, that is to say they are very light diameter, or about one-sixteenth that of - the heaviest of them is only a fortieth the earth. Its volume would thus comthe weight of the earth, while the lightest prise sixty-five millions of cubic miles of is but a two-hundredth. Had the comet matter, about one-eightieth of the volume which traversed them been of any respect- of the moon; and if the comet was not able weight he would have made havoc composed of denser or heavier matter among them and bouleversed their motions. than our satellite, its mass or weight But it was a case of locomotive and cow, would be one-eightieth of the moon's, and and it was "bad for the coo." Although its gravitational effect, at the same distance, in mere size the comet was reckoned to be as small in proportion. Had either this about ten times as large as the greatest comet or Lexell's come as close to us as of the Jovian satellites, yet its mass was the moon it would scarcely have exercised so paltry that it produced no effect what- any appreciable influence on the tides or ever upon these little moons, but, on the any other phenomenon or condition which other hand, was itself enormously influ- can be affected merely by the mass or enced by their primary, having been held gravitational power of a proximate body. captive for four months under Jupiter's Certainly the comet in either case could sway, and in the end completely diverted not have made us its prisoner and carried from its former orbit and sent off upon us away into infinite space, or led us inanother and a totally different one. wards to make fuel for the sun, or to be cindered by close contiguity to the luminary; and this was of old one of the dreaded consequences of a cometary approach.

There is another fact in connection with this comet which still more closely concerns our present discussion. On the 1st of July, 1770, it actually approached the earth within six times the distance of the moon. Now if the comet had been as great in weight-mass as the earth, Laplace has shown that it would at this distance have so disturbed the earth's orbital motion as to have lengthened the sidereal year by two hours and forty-seven minutes. But it is known that this period does not differ now by so much as two seconds from what it was before the comet came near us, and two seconds is but the five-thousandth part of two hours fortyseven minutes; and since the comet did not produce one-five-thousandth of the effect that it would have had it equalled the earth in mass, it is inferable that its mass was not equal to one-five-thousandth of that of the earth. This deduction tends to set at naught the alarming conclusions before alluded to which were arrived at by assuming a comet's weight to be nearly equal to that of our globe.

But there are comets and comets, and it may be urged that we cannot conclude they are all alike small and gravitationally powerless. Lexell's, however, was, to say the least, a fair sample. When it came nearest to us the measured diameter of its sphere of nebulosity (for it had no tail) was 59,000 miles, or five times the size of the moon. Its nucleus, which was very bright, had a tenth of this diameter, or nearly 6,000 miles. The memorable comet of 1858, (Donati's) vast and brilliant as was its vaporous surrounding, was corporeally smaller than Lexell's. Its solid () portion, its nucleus, was measured, and found to be at most only 500 miles in

But may not a comet itself be such a fiery furnace as to affect us scorchingly, if it should but pass near us? We are hardly prepared to answer this question, in the present state of our knowledge. If only a good comet would make its appearance, no doubt some information would be speedily acquired concerning its thermal conditions; for in recent years an instrument has been used for measuring the radiant heat of the moon and stars, which no one had thought of applying when last a bearded star visited us. We allude to the thermo-electric pile- the thermometer, for such it is, is so wonderfully sensitive that it will detect differences of temperature amounting only to a few millionths of a Fahrenheit degree. If another Donati would but exhibit itself we should doubtless soon have grounds for fairly judging whether a comet be an accumulation of hot combusting matter, or merely a body of cool substance glowing by some such property as phosphorescence. This, however, we have learnt within the past four years, thanks to the revelations of the spectroscope: that the light of several small comets which have appeared within this period has been identical with that emitted by the highly heated vapour of carbon. This shows cometary matter, so far, to be largely carbonaceous. But how comes the carbon into a state of apparently hot vapour? Some comets, it is true, have been known to approach the sun sufficiently near to acquire the fervent heat requisite to vaporize carbon; but this could hardly have been the case with the comets in question. The difficulty is removed if we assume that the

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