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are, of course, speaking of the average | ible with the supposition that the law of density of the star. No doubt its central gravitation prevails throughout the uniportions must be dense enough, but it is verse. It would not, however, be correct impossible to resist the conclusions that to assert, as has been sometimes done, the greater part of Algol must be composed that the facts of the binary systems of matter in a gaseous state. Of course, actually prove that gravitation is the allsuch a state of things is already known to compelling force there as here. The exist in many celestial bodies. The fig- circumstances do not warrant us in exures that have been arrived at must be pressing the matter quite so forcibly. The regarded as subject to a possible correc- binary stars are so remote that the obser tion, but it is difficult to repress all feelings vations which we are enabled to make are of enthusiasm at a moment when, for the wanting in the almost mathematical prefirst time, so startling an extension has cision which we can give to such work been given to our knowledge of the uni- when applied to the bodies of our own verse. And now, as to the dark compan-system. It is quite possible for matheion of Algol. Here is an object which we matical ingenuity to devise a wholly arbinever have seen, and apparently never can trary and imaginary system of force, expect to see, but yet we have been able which might explain the facts of binary not only to weigh it and to measure it, but stars, as far as we are able to observe also to determine its movements. It ap- them, on quite another hypothesis than pears that the companion of Algol is about the simple law that the attraction between the same size as our sun, but has a mass two particles varies with the inverse square only one-fourth as great. This indicates of the distance. No one, however, will be the existence of a globe of matter which likely to doubt that it is the law of gravimust be largely in the gaseous state, but tation, pure and simple, which prevails in which, nevertheless, seems to be devoid of the celestial spaces, and consequently we intrinsic luminosity. We may compare are able to make use of it to explain the this body with the planet Saturn; of circumstances attending the movement of course, the latter is not nearly so large as Algol's dark companion. the companion to Algol, but the two globes This body is the smaller of the two, and seem to agree fairly well as to density. the speed with which it moves is double As to the character of the movements of as great as that of Algol, so that it travels the dark companion of Algol, we can learn over as many miles in a second as an exlittle, except what the laws of dynamics press train can get over in an hour. It may teach; but the information thus ac- revolves with apparent uniformity in an quired is founded on such well-understood orbit which must be approximately circuprinciples that it leaves us in no uncer-lar, and it completes its journey in the tainty. It would be a natural assumption that the law of gravitation is obeyed and must be obeyed in the stellar systems. It would, indeed, be surprising if that law which regulates the movements of the bodies in the solar system should not be found to prevail in the sidereal systems also. Everything would justify us in the anticipation that this is so. Have we not learned to a large extent the actual nature of the elementary bodies which enter into the composition of stars? We find that the ingredients of these other suns are in the main identical with those which exist in our own sun and in the earth itself. If iron attracts iron by the law of gravitation in the solar system, why should not iron attract iron in the sidereal systems as well? But we are not dependent solely on this presumption for our knowledge of the important fact that the law of gravitation is not confined to the solar system. The movements of binary stars have been studied, and it has been invariably found that the phenomena observed are compat
brief period given above, which indicates
proportion to their distance apart when | ciation of Alcor and Mizar is rendered compared with the more familiar planets and satellites of our system. The tides in such a case must be of a magnitude and importance of which we have no conception from our experiences of such agencies here.
We have dwelt thus long on the subject of Algol because it was fitting to give due emphasis to the remarkable extension of our knowledge of the universe which took place when, for the first time, we became able to measure the size of a
highly probable from the fact that they move together in parallel directions and with the same velocity. But this is the least of the circumstances that gives Mizar its interest. The star itself is a double of the easiest type, and is at the same time of striking interest and beauty. Every possessor of a telescope, large or small, knows Mizar to be one of the most suitable objects wherewith to delight the friends that visit his observatory, by a glimpse at a double star which is both easy to discern and remarkable in character. This is the second noteworthy point about Mizar; but now for the third and last, which is by far the most interesting of all, and has only lately been ascertained by a discovery which will take its place in the history of astronomy as the inauguration of a new process in the study of things sidereal.
It is well known that the most difficult test-objects on which a telescope can be directed are some of those double stars of which the components have a suitable distance. If the two stars be so close to gether that they subtend at our system an angle not more than a few tenths of a second, then the telescopic separation of Professor Pickering has, as is well the two components is a feat to tax the known, been extremely successful in obpowers of the most perfect instrument, taining photographs of the spectra of the and the eye of the most accomplished ob- stars. Sufficient means having been server. It may, however, happen that placed at his disposal by Mrs. Draper, he there are double stars of which the compo- has applied himself with remarkable renents are much closer than this. In such sults to the compilation of the Henry a case there is not the slightest possibility Draper Memorial. The photographs of of our being able to effect a visual decom- the spectra of the stars that he has thus position of the pair into its components. obtained exhibit a fulness of detail that The spectroscopic process has, however, some years ago could hardly have been placed at our disposal a striking method expected even in photographs of the solar for detecting the existence of double stars, spectrum itself. Among the stars subso extraordinarily difficult that even if thejected to his camera was Mizar, and the components were hundreds of times far- photographs of the spectrum of its princither apart than they actually are they pal component exhibited, as other stellar would still fall short of the necessary dis- spectra did, a profusion of dark lines. tance at which they must be situated be- These photographs being repeated at diffore they can be separated telescopically. ferent dates, it was natural to compare Indeed, we have here obtained an acces- them together, and it was noticed that the sion to our power so remarkable that we lines sometimes appeared double and have not yet been able even to feel the sometimes single. So striking a circumlimits within which its application must be stance, of course, demanded closer invesconfined. As an illustration of this proc-tigation, and presently it appeared that this ess I shall take a star which is probably as famous as Algol itself. It is Mizar, the middle star of the three which form the tail of the Great Bear. Mizar has in its vicinity the small star Alcor, which is now so easily seen as to make it hard for us to realize the significance of the proverb, "He can see Alcor." It is, however, possible that the lustre of Alcor may have waxed greater since ancient times. The relationship between Mizar and Alcor is closer than might be inferred from the mere fact of their contiguity on the sky. Their proximity is not an accident of sit uation, as is the case in some other instances when two stars happen to lie in nearly the same line of vision. The asso
opening and closing of the lines was a periodical phenomenon. The interval between one maximum opening of the lines and the next was fifty-two days. If the star were a single object, then this phenomenon would be inexplicable. It was plain that the object could not be a single star; it must consist of a pair extremely close together, and in rapid revolution. The doubling of the lines will then be readily intelligible. When one of the components is moving towards us while the other is moving from us, all the lines belonging to one system are shifted one way, and all those belonging to the other system are shifted the other way, the effect on the spectrum being that the lines ap
pear doubled. When the stars are moving perpendicularly to the line of sight, then their relative velocities towards the earth are equal, and the lines close up again. We thus at once learn the period of the revolution of the two components. The lines must open out twice in each circuit, and consequently we have as the first instalment of the numerical facts of the system that the period of its revolution is a hundred and four days. It is, however, a peculiarity of the spectroscopic process that it provides us with a wealth of information on the subject. The amount by which the lines open when they separate admits of accurate measurement, and as this depends on the velocities, it follows that we obtain a determination of these velocities. It thus appears that the speed with which each of the component stars moves is about fifty miles a second. As, therefore, we know the pace at which the stars are moving, and the time they need for the journey, we know how large their path is, and thus we infer that the distance of the components is, speaking roundly, about one hundred and fifty millions of miles. But now we are enabled to draw a remarkable inference. We know the size of the orbits, and we know the time in which the revolutions are accomplished. It is the mathematician who enables the mass of the bodies to be determined, and the result is not a little astonishing. It tells us that the mass of the two component stars which form Mizar is not less than forty times as great as the mass of the sun. Here is indeed a result equally striking on account of the method by which it is obtained and of the startling character of the conception to which it leads. Remember that in all this the distance of the star from the earth is not concerned, for the results at which we have arrived are absolutely independent of the distance at which the star may happen to be placed. We already knew the masses of some few binary stars by the application of the older process, but in all such cases it was necessary that we should have a previous knowledge of the star's distance. This is always a precarious element, and in the majority of cases it is wholly out of our power to discover it. Now, however, we are entitled to expect large additions to our knowledge of the stars, their masses, and their movements, notwithstanding the fact that the distances may be too vast to be appreciated by any means at our disposal.
The instances that have been given will suffice to show the versatility of the new
method. It is the alliance of photography with spectroscopy that makes the present time so full of promise. The improvement of the two arts has gone on simultaneously, and the quantity of detail that is contained in such photographs of stellar spectra as those which have been recently obtained by Professor Pickering and by Mr Lockyer shows the immensity of the field that now invites exploration.
ROBERT S. BALL.
From The Cornhill Magazine. THE VICAR'S SECRET. THE windows at the rear of Acton Chase, an old house in Worcestershire, look out on a quaint bowling-green flanked by yew hedges, and backed by a stream of good size, on the farther side of which a sparsely timbered slope leads up to the home farm, and to half-a-dozen farms be sides, which once formed the Chase. Zigzag up this slope runs a trackprobably it has so run for centuries, for at the foot of it is a good ford - which in spring is almost invisible, but in autumn is brown and rutty. The Chase has long been a Roman Catholic house, and up this track dead-and-gone squires, debarred from much converse with their neighbors, have gone to hunt, mornings innumerable; so that even to-day people sitting in the garden towards evening are constantly seeing them come trailing home, their horses jaded, and themselves calling for the black-jack.
Our story, however, is not of these, but of two men who strolled down this path on an evening no farther back than last August. They seemed, outwardly at least, ill-matched. The one, a young fellow under thirty, fair-haired and pink-cheeked, and somewhat prim-looking, was of middle size. He was dressed as a clergyman more neatly and trimly, perhaps, than the average country clergyman dresses. The other was probably the tallest and thinnest man ever seen outside a show-a man whose very clothes, his worn jacket, and shrunken knickerbockers, seemed to share his attenuation. He looked like a gamekeeper, but was, in fact, the squire's son-in-law, Long Jim Foley.
"I really cannot make you out," he said, as the two sighted the house; and, shifting his gun to the other shoulder, he took occasion to glance comically at his companion. "What do you do, old boy? You never kill anything, unless it is a
trout now and then. live without killing. every day!"
Now, I could not | note, was no delusion. Satisfied, he rose
"And do you?" "Seldom miss," rejoined the long man cheerfully, "except on a hunting day when we draw blank. Rats, rabbits, otters, pike, sometimes a hawk, sometimes, as to-day, a brace of wood-pigeons. And game and foxes in their season. Must kill something, my boy."
His companion glanced at him askance, looked away again, and sighed.
"I say, what is that for?" Foley continued, in the tone of an aggrieved man.
"I was only thinking," replied the other dryly, "what a lucky fellow you were to have nothing to do but kill, Foley. That is all."
The tall man whistled. "I say," he said, "for a man who is going to be married in a week or so, you are in roaring spirits, ain't you? I will tell you what it is, my boy; you do not take very kindly to your bliss. I can see Patty flitting about in the garden like a big white moth, waiting, I have no doubt, for a word with your reverence; and your step lags, and your face is grave, and you incline to be cynical! What is up?"
The younger man laughed, but not very merrily; and there was a touch of sullenness in his tone as he answered, "Nothing! A man cannot always be grinning." No; but pâté de foie gras is not a man's ordinary meat," retorted Jim imperturbably. Jones!"
"Well?" said the other snappishly. "You are in a mess, my boy - that is my opinion! Now, don't take this amiss," Jim continued with dry patience. "I am within my rights. I am one of the family, and if the squire is blind and Patty is inexperienced, I am neither. And I am not going to let this go on until I know more, my boy. You have some tie or other which weighs on your mind and of which they are ignorant."
The young clergyman turned his face to his companion, and Jim Foley, albeit a very cool personage, was taken aback by the change which anger or some other emotion had worked in it. Even the clergyman's voice was altered. "And what if I have?" he said hoarsely, stopping short so suddenly that the two confronted one another. "What if I have, Mr. Foley?"
"Will not, you mean."
"No, cannot, cannot!" replied the clergyman with vehemence.
"Then," Jim drawled, "I'm not a moral man, don't mistake me for a moment, but I belong to the family your majesty must go elsewhere for a wife! And a little late to do so!" he continued, a hard ring in his tone. "What! you are not coming to the house?"
"No" cried the other violently. And without more, without a word of farewell, he turned his back and strode away through the lush grass to a point a little higher up the stream, where a plank bridge gave access to the Chase outbuildings, and through them to the village.
Foley stood awhile looking after him. "Well," he said at last, speaking gently, as if rallying himself on some weakness, “I am afraid — I really am afraid that I am a little astonished. I should know men by now, and yet I did think that if any one could show a clean bill of health it was the vicar. He is smug, he is almost a prig. The old women swear by him, and the young ones dote on him. They say he is on foot from morning till night, and not one blank day in a fortnight! And - pheugh! I wonder whether I ought to have knocked him down. Poor little Patty! There is not a better girl in the county except the Partridge !"
He looked down almost pathetically at the gardens below him, but, seeing that the chimneys of the house were smoking briskly, bethought him of dinner, and strode down to the gate with his usual air of perfect insouciance.
Meanwhile the young clergyman gained the side avenue, and walked on rapidly towards the village, his eyes dazzled by the low beams of the sun which shone directly in his face, and his mind confounded by the tumult of his own thoughts. A crisis which he had long foreseen and dreaded, and as often postponed, was now imminent, the power to control it gone from his hands. He looked on the past with bitter regret, and forward with shame as great. That which had once been feasible-nay, as it seemed to him now, Jim deliberately shut his eyes and almost easy time and he had rendered opened them again, to make sure that the impossible. He stood aghast at his own tragic spirit, so suddenly interposed be-feebleness, not considering that the routine tween him and the pleasant landscape, of parish work and the satisfaction accruwith its long shadows and distant forge- ing from small duties done - the doing of
which had after all been no self-sacrifice, vicar, with his back against the door, no effort - had weakened his moral fibre, looked at him and shuddered, and then even as the peacefulness of the life about looked again, his face hard and his eyes him, and the transparent truthfulness of gloomy. "Well?" he said, in a low, stern those with whom his lot was cast had voice, "what is the meaning of this? made the task of disclosure more formi- What do you do here? You know our dable. He had fallen-no, he had not agreement. Why have you broken it, fallen, but he had put off the act which sir?" honor demanded so long that, though the day of grace was still with him, there could be no grace in the doing of it.
The rooks, streaming homeward in some order of their own, were cawing overhead as he opened the gate and entered the vicarage garden, where the great hollyhocks stood in rows, and the peaches, catching the last rays of the sun aslant, were glowing against the southern gable. To the stranger to the American, in particular who looked in as he passed, it seemed a paradise, that vicarage garden. But for peaches are not peace, nor hollyhocks either-its owner passed through it with compressed lips and cheeks still tingling. He entered the porch, where one or two packing-cases told of coming changes, and then stood irresolute in the cool, silent hall, remembering that he had intended to dine at the Chase, and that probably there was nothing prepared for him here. Not that he had any appetite, but dinner was a decent observance, and it seemed to him just then that not to dine at all would be to lose his hold on his present life and fall into unknown abysses before his time.
It is well, when we are badly off, to consider how much worse off a minute, a few seconds, may see us. A faint sound at his elbow caused him to turn towards the dining-room. The door was ajar, and through the opening a face was looking out at him. The young vicar did not start, but he drew a deep breath, and seemed to stiffen as he gazed. A minute, and his lips while the other face, with a shifty smile, half mockery, half shame, returned his look-formed the word "Father!"
It was not audible two paces away, but as it fell the clergyman glanced round with a stealthy gesture of alarm, and at a single stride was in the dining-room and had shut the door behind him. The other man a shambling, bent creature, grey-haired and blear-eyed and unwashed, with a beard of a week's growth on his chin- fell back to the table and leaned against it. His rusty black clothes and his boots, broken and dusty, seemed to partake of, rather than to impart, the look of decay and misery which marked his person. The
The old man pursed up his lips, and, with his head on one side, contemplated his questioner in silence. Then he said suddenly, "Blow the agreement!"
The vicar winced as if he had been struck, but he found words again. "If you can do without the money," he said, "so much the better; but
"Blow the money!" cried the old man, with the same violence. Notwithstanding his words, he seemed to stand in awe of his son, and to be trying to gain courage by working himself into a passion. "What is money?" he continued. "I want no money! I am coming to live with you. Oh, yes, you are going to be married. I heard of it, though you kept it close, my boy! I heard of it, and I said to myself, Good; I will go and live with my boy, and his wife shall take care of my little comforts.""
The younger man shivered. He thought of Patty, and he looked at the old man before him, sly, vicious, gin-sodden — and his father! "You do not want to live with me," he answered coldly. "You could not bear to live with me for a week, and you know it well. Will you tell me what you do want, and why you have left Glasgow?"
"To congratulate you!" the father an swered, with a drunken chuckle. "Walter Jones and Patty Stanton-third time of asking, you know! Oh, I heard of it! But not through you. Why," he continued, with a sudden change to ferocity, "would you not ask your own father to your wedding, you ungrateful boy?"
"No," replied the vicar sternly and almost loudly, "he being such as he is, I would not."
"Oh, you are ashamed of him, are you? You have kept him dark, have you?" replied the old man, grinning with wicked enjoyment as he saw how his son winced at each sentence, how the color went and came on his cheek. "Well, now you will have the pleasure of introducing me to the squire, and to daughter Patty, and all your friends. It will be a pleasant surprise for them. I dare say you said I was dead."
"I have not said you were dead." "Don't you wish I was?"