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of the Pyramids! This fact should be suggestive to cessor, who may, probably, turn and “ Chin, chin!” summer tourists in search of an object.

to the original inventor of the story in Pekin! It is singular to find how soon stories became old, Although most of the ancient Greek traits of even in early times. Even the exclamation of Joe simplicity have been transferred in modern times to Miller!” to indicate a venerable joke, is as old in Irishmen, the Scots have come in for a share, not sense, if not in sound, as the days of the father of only taking the joke, but naming a Scottish indiAlexander the Great. When Philip was the Mace-vidual as the hero of it. One of the ancient stories donian king, there was a club of wits in Athens in Hicrocles is thus appropriated in the north : which met once a week, not in the tavern, but the · Duncan M'Girder wanted to use his mare, by temple of Hercules. They had such a favorable degrees, to live without meat, and just as he had opinion of their own powers, that they chronicled put her on a straw a day, the poor thing died.” all their own jokes, and kings sent to borrow the This is the Hierocles story wbich was appropribook — " The Book of the Sixty," it was called, ated and made a fable of by the writer who is from the number of the members – when they known to us as Æsop, and which has been transwere depressed by the turn of politics, or by their planted into every country in the world. There own humors, and stood in need of a laugh and its would really seem to be nothing new; train ways refreshing influences.

are found in Thebes and Memphis; the balloon Very many “ good things" must have been en flies in idea through many a classical story ; the tered in this proto-jest book, though we do not telegraph, under another form, fashed intelligence know what they were. For a time they served the from one district to another of the ancient world; purpose of " diners-out," and of men who carried no and even our choicest classical traditions have variwit about with them, save what was contained in ous hones. When Europeans first arrived among their memory of the wit of others. The volume, the New Zealanders, they found Hero and Leander however, became so familiar through its contents a local legend, with the slight difference that it was being circulated abroad, vivâ voce, that the hearers the lady who dashed through the flood to meet the at last got weary of it, and whenever a dull fellow dusky lover, who quietly held the lamp to guide sought to derive some brilliancy by repeating one her to the trysting-place. of the oft-told stories, he was met by a general cry. There is something very singular in the way in of “Come, that's an old Sixty !” And our best which errors still spring up, like weeds, on the spot jokes are pretty well as old as the volume in ques- where the original seed was sown. Not many tion. For example, we ascribe to Theodore Hook inonths ago, the Times' correspondent in Paris comthe merit of mischievous originality in the" Berners municated to that paper the translation of a letter Street Hoax," whereby he brought a thousand or which had just appeared in a French provincial two of people, besides horses and carriages, into one journal, as an illustration of the simplicity of the street, and making towards one house, at one and modern Gaul. The sample was afforded by a let'the same moment. Now, the honor of originality ter, allegedly written by a soldier in hospital to his in this matter belongs to one Ciphisodorus, who ad- colonel, who had sent to the invalid the news of his vertised for thousands of day-laborers to repair to a father's death. The soldier's epistle was to this certain street in Egypt, at a certain hour. This effect : “ Colonel : I thank you for the death of wag enjoyed from a secure hiding-place all the my father. It's an accident, like any other; let "fun" be expected from witnessing the confusion us hope, however, that it will have no bad conin a narrow street caused by crowds of disappointed sequences. ....I have just broken my leg, with men fighting their way out against crowds of hope- which I have the honor to be, your very obedient ful men fighting their way in.

servant !” Now, this sample of modern French There is scarcely a modern illustration of witty simplicity and humor is as old as the oldest French or humorous Irish simplicity which is not, at least, ljest-book, and that will give it an age of several as old as the Platonic philosopher of Alexandria, centuries. Hierocles, who lived five centuries before the Chris- But authors, journalists, and critics at home tian era. At that early period men laughed at the occasionally err, even like their brethren abroad. simpleton who resolved never to go into the water | The Examiner recently reviewed a book called till he had learned to swim; or at him who wished " The Campaigner at Home," by Shirley. In that himself as speechless as the sick man from whom he book the author states that a clergyman — a friend could obtain no reply, in order that he might return of his – had assured bim that he had recently met the invalid's incivility; or at that other who at- with a sample of ignorance which had sorely distempted to keep his horse alive without food, and tressed him. Encountering a stranger girl in his who failed just at the moment of success by the parish, the clergyman asked her whose child she obstinate brute dying. Greeks laughed, long before was; to which she answered that she was - the Irishmen, at their respectively alleged fellow-coun- child of wrath"; and on being asked where she tryn:an who carried à brick about as a sample of .was born, she as readily replied, “ born in sin." the house he had to sell. The Hibernian who Now, what a respectable clergyman relates, to an shut his eyes before a looking-glass, that he might equally respectable author, as a trait of his recent see how he looked when he was asleep; who bought experiences, must be true; but the singularity is, a crow, to test the truth of the assertion that the that the Examiner, whose critics are not wanting in bird lived a couple of centuries; who, in a ship acuteness and long memories, should not have been wreck, clung to an anchor, to save himself from aware that this story, now cited by it as new, apdrowning; and who remarked to a friend who rea-peared in its own columns between forty and fifty sonably denied the asserted fact of his reported years ago. If I mistake not, the invention of it is death, that the fact had been vouched for by one due to the felicitous humor of Leigh Hunt. who was more worthy of credit than he who denied. There is a story told of Dr. Johnson, in which he it, - that Hibernian is an old Greek in modern is represented as referring to a literary friend, who guise, and the Greek, as in the story of Ampbit would seem to have lacked the usual modesty by ryon, is believed to be indebted to a Hindoo prede- which literary men are distinguished. This is illustrated by Johnson's remark to another friend : stay. What is told of him subsequently is remark“Sir, I never did the man any harm, yet he would ably like the following story in “ Richardsoniana": read his tragedy to me!” As human nature has been “Very often the taste of perpetually running of much the same quality in all ages, it is possible after diversions is not a mark of any pleasure taken that this anecdote may be true, but it closely re- in them, but of none taken in ourselves. This sal i sembles, with a difference, one told by Horace, of a lying abroad is only from uneasiness at home, which certain Drusus, who combined the very opposite is in every one's self. Like a gentleman who, overvocations of historian and money-lender. This looking them at White's, at picquet, till three or four Drusus, when a debtor came to excuse himself, on in the morning, on a dispute, they referred to him. the “ gloomy calends," for not having prepared to When he protested that he knew nothing of the pay principal, or perhaps even interest; used to game,' Zounds !' say they, and sit here till this make the poor wretch sit down, and, with slavishly time?' Gentlemen, I'm married !' •0, sir, we outstretched neck, listen, while his creditor read beg pardon !'” It was so with the French duke: aloud to him his prosaic passages of history. he married that he might stay at home; and it was

If old jokes thus repeat themselves, old customs, just then he discovered that he could not abandoa too, have a wonderful vitality. In Blunt's “ Ves- his old habit of going out, and accordingly he stayed tiges,” we find that, among other old Italian observ- abroad late because he happened to be married. ances, that of demanding payment of debts on the first of every month is retained by some of the modern Italians. “I was assured by a Roman gentle

COLORED SUNS. man,” says Blunt, "with very great feeling, that BY RICHARD A. PROCTOR, B. A., F. R. A. S. the epithet “tristes calendas' was never more appli | IF a brilliant star be observed when near the cable to the calends than at this moment."

horizon, it will be seen to present the beautiful pbe To Dr. Johnson, by his biographer; to Lord nomenon of " colored scintillation." The colors thus North, by Earl Mount-Edgecumbe; and to Monk exhibited exceed in purity even those seen in the Lewis, by the Rev. Philip Smith (in his “ Encyclo- solar spectrum or in the rainbow. By comparison pædia of Wit”), is assigned the paternity of a re- with them the light which flashes from the ruby, the mark which is believed to be as old as the Tudor emerald, the sapphire, or the topaz, appears dull and period, if not older. According to some chroniclers, almost earthy. There are four or five stars which an acrobat was going through some thrilling feats present this phenomenon with charming distinctnes. on the rope; according to others, a violinist was The brilliant Vega in the constellation Lyra, which performing a wonderful achievement on his instru- rarely sets in our latitude, is one of these. At midment; according to Lord Mount-Edgecumbe, Cata- night in winter, and earlier with the approach of lani was performing a tour de force in vocalization, spring, this splendid steel-blue star may be seen as when, to the comment that it was “difficult," came it skirts the southern horizon, scintillating with red, the reply, “ Difficult! I wish it were impossible!” and blue, and emerald light. Arcturus twinkles yet Lord North was as likely to have made such a reply more brilliantly low down towards the northeast in as any one. He had more practice of wit than he our spring evenings. Capella is another notable possessed love for music; and when he was asked to scintillator, seen low down towards the north during join his brother, the Bishop of Winchester, in sub- the summer nights. But these, though they are the scribing to the “ Concerts of Ancient Music,” he most brilliant northern stars, yet shine with a splenanswered, “I would do so most readily if I were dor far inferior to that of Sirius, the famous dor. only as deaf as my brother!”

star. No one can mistake this noble orb as it rises Lord North did not become deaf, but blind. The above the southern horizon in our winter months. same affliction visited his old political opponent, The vivid colors exhibited by Sirius as it scintillates, Colonel Barré. The two antagonists were brought have afforded a favorite image to the poets. Homer face to face with each other in the Assembly Rooms compares the celestial light which gleamed from the at Bath, long after their season of warfare was over. shield and helmet of Diomed to the rays of “ Sirius, Lord North was the wittier man, and he said with the star of autumn," which “shines with a peculiar great readiness, “ Colonel, I should be as glad to see brilliancy when laved by ocean's waves"; and, to you as you would, I am sure, be happy to see me, pass at once from the father of poetry to our greatwhich is more than we should have felt or said in the est modern poet, we find in Tennyson's “ Princess" old days.” Something like this is told of blind old the same image, where he says of Arac and his Madame de Deffand and a friend “ with the sight- brothers, that less orbs "; and there is a French (alleged) origin

"As the fiery Sirius alters hue, to many of our good stories. The question is not And bickers into red and emerald, shone what date is assigned to an old story now, but what Their morious, washed with morning, as they came." is the date of the oldest recorded edition of the It is difficult to persuade one's self that these ever story. Only the other day some praise was given changing tints do not really belong to the stars. But to a dissenting preacher for inventing such a happy there is now no doubt that they are caused by our word (infelicitously called so) as “ingemination"; lown atmosphere. Unequally warm, unequally but the readers of Horace Walpole know that the dense, and unequally moist in its varions strata, the word was used by him in his letters, and they prob- air transmits irregularly those colored rays which ably think that it has no more claim to be admitted together produce the light of a star. Now one colo into the English language than the "anfractuoşi- or prevails over the rest, and now another, so that ties” of Dr. Johnson.

the star appears to change color. But it is only Some stories, doubtless, repeat themselves acci- low down towards the horizon that these changes dentally. There is one of an old French duke who take place to their full. extent. In the tropics, used nightly to visit an old French countess to play where the air is more uniform in texture, so to speak, picquet with her, but he found this so inconvenient the stars do not scintillate unless they are quite in winter, as he had to return home, that he pro- close to the horizon, “a circumstance," says Hamposed marriage, in order that he might decently | boldt, " which gives a peculiarly calm and serene

character to the celestial depths in those coun- of color, that we may trace the presence of a law tries."

of distribution, if such exist. But the stars are not wanting in real colors, caused! We have said that blue stars are not met with by peculiarities in the quality of the light which singly in the heavens. Among double stars they they emit towards us. In tropical countries the col- are common enough. But they are generally small. ors of the stars form a very obvious and a very When the larger star or primary is not white it is beautiful phenomenon. The whole heaven seems usually either red or yellow; then the smaller star set with variously colored gems. In our latitudes, — or satellite, as we may term it - is frequently none but the brightest stars exhibit distinctly marked | blue or green. But this is so far from being a law colors to the naked eye. Sirius, Regulus, and Spica without exception that the more common case is to are white stars; Betelgeux, Aldebaran, Arcturus, find both stars similarly tinted. Amongst 596 bright and Antares are red; Procyon, Capella, and the “doubles," Struve found 375 whose components Pole-star are yellow; Castor exhibits a slightly were similarly colored, 101 whose components pregreen tint; while Vega and Altair are bluish. An- sented colors belonging to the same end of the tares which we have described as a red star, pre- spectrum, and only 120 in which the colors were sents when carefully watched a greenish scintillation totally different. so peculiar as to have early attracted the notice of Amongst double stars whose components are astronomers. The green tint of Castor bad been similarly tinted, by far the greater number are found to arise from the fact that the star is double, white, yellow, or red. But there are some instances and one of the components green. But, for a long of double blue stars; and there is in the southern while, powerful instruments failed to exbibit a com- heavens a group containing a multitude of stars, all panion to Antares. At length General Mitchell, | blue. with the great refractor of the Cincinnati Observa It is impossible, therefore, to suppose that the tory, detected a minute green companion to this blue colors seen in multiple systems are due to the brilliant red star, — the Sirius of red stars as it has mere effect of contrast. In some cases this may been termed.

happen, however; or at any rate the effect of conBut as we have said, the stars which present dis- trast may intensify the colors of each component of tinctly marked colors to the naked eye in our lati- a “complementary double.” There is one very tudes, are few and far between. It is in the tele- charming instance of complementary colors in a scope that our observers have to seek for a full view double star which may be separated with a telesof the delicate plenomenon of colored stars. cope of very low power. We refer to the star When a survey is made of the heavens with a pow- Albireo on the beak of the Swan. The compoerful telescope, peculiarities well worthy of careful nents of this star are orange and blue, the tints attention are revealed to the observer. We have being well pronounced. It has been found that seen that there are no stars visible to the naked eye when one of the components is hidden the other still which are decidedly blue or green. The ancients, preserves its color, though not quite so distinctly as also, recognized only red and white stars. In the when both are seen together. Another " completelescope, this peculiarity is still observable when mentary double" is the star y Andromedæ. The single stars only are looked at. We meet with primary is red, the smaller star green. In very some telescopic stars the depth of whose red color powerful telescopes the smaller component is found is remarkable. There are stars of a fiery red, of a to be itself double, and doubts exist among astrondeep blood-red, and of a full orange color. There is omers whether the two minute components of the a well-known star entitled the “ garnet star.” And, lesser star are both green, or one blue and the other in fact, every variety of color, from white through yellow. There is another double star very beautiyellow and orange to a deep almost dusky red, is ful in a powerful telescope. This is the stare met with among the single fixed stars. But there Boötis, on the Herdsman's belt; it is called also is no instance throughout the whole heavens of a Mirach, and on account of its extreme beauty Pulsingle green, blue, or violet star.

cherissima. The components are nearly equal, The case is altered when we come to examine orange, the other a delicate emerald green. those double, triple, and multiple stars, the observa One of the most startling facts revealed by the tion of which is one of the most pleasing employ-careful observation of the fixed stars is that their ments of the amateur telescopist.

color is not unchangeable. Amongst these systems we meet with all the tints We may begin at once with the brightest of the of the rainbow, and with many colors which are not fixed stars, — Sirius. This star was known to the seen in the rainbow, such as fawn-color, lilac, gray, ancients as a red star. To its fiery hue may doubtand so on. “ The attentive observation of the less be ascribed the peculiar influence assigned to double stars," writes the celebrated Struve (who it by ancient astronomers. At present Sirius is detected 3,000 of these objects), “teaches us that brilliantly and unmistakably white. besides those that are white, all the colors of the We have not such decisive evidence in the case spectrum are to be met with.” “Here we have a of any other noted star. But among telescopic green star with a deep blood-red companion, there stars, there have been some very remarkable an orange primary accompanied by a purple or in-changes. There are two double stars, described digo-blue satellite. White is found mixed with light by the elder Herschel as white, which now exhibit or dark red, purple, ruby, or vermilion." Some-golden-yellow primaries and greenish satellites. times a single system offers at one view many dif- | That careful observer, Admiral Smyth, records ferent colors. Such is the case with the remarkable also that one of the components of a double star group detected by Sir John Herschel within the in Hercules changed, in twelve years, “ froin yellow, Southern Cross. It is composed of no less than 110 through gray, cherry-red, and egregious red, to stars, which, seen in a telescope of sufficient size, yellow again." appear, Herschel tells us, like " a casket of variously | The questions may well be asked, whence do the colored precious stones."

stars derive their distinctions of color ? and by what It will be well to examine some of the collocations processes do their colors change? To these ques

tions modern discoveries have supplied answers This last circumstance is well worthy of notice, which, if not complete, are well worth listening to since it is a peculiarity characteristic of while stars,

It had long been suspected that the stars are in — so that we begin already to find a bint respecting reality suns. It had been shown that their distance the source of color or of the absence of color in from us must be so enormous as to enable us to stars. assign to them an intrinsic brilliancy fully equal in Take next an orange-red star, the brilliant Betel. somne instances, and in others far superior, io that geux. The spectrum of this star was very carefully of our own sun. Nothing remained but that we analyzed by Messrs. Huggins and Miller. Ther should have some evidence that the kind of light marked down the places of two or tbree hundred they emit is similar to that which we received from lines, and measured the position of no less than the sun. This evidence has been supplied, though eighty. They found that sodium, magnesium, calonly of late years.

cium, iron, and bismuth are pre.ent in the star's atWe cannot here enter at length into an account mosphere, but the two strong lines which note the of the important discoveries of Kirchhoff and Bunsen presence of hydrogen are wanting. which have enabled astronomers to analyze the Take next the yellow star, Pollux. The observlight emitted from the celestial bodies. It will be ers were not able to obtain very satisfactory meas sufficient to remark that in the solar spectrum there ures of this star ; but they established the presence are observed fine dark lines breaking the continuity of sodium and magnesium in the star's atmosphere; of the streak of light, and that these lines have been and again the strong lines of hydrogen were found proved to be due to the presence of the vapors of to be missing. certain elements in the solar atmosphere. The But we are not entitled to assume that red and proof depends on the exact correspondence of num- yellow stars are characterized by the absence of bers of these lines, grouped in a complex manner | hydrogen from their atmospheres. On the con(so as entirely to eliminate the possibility of a mere trary, the noted red star Alderbaran, the spectrum chance accordance with the bright lines seen in of which was very carefully analyzed by Huggins the spectra of light from the vapors of those ele- and Miller, was found to exhibit the two lines ments. When once Kirchhoff and Bunsen bad of hydrogen with perfect distinctness. This star proved the possibility of exhibiting the same set of exhibited a richness in the construction of its atmoslines either as bright lines on a dark ground or as phere not presented by any other. The elements dark lines on a brilliant spectrum, all doubt as to proved to be present are sodium, magnesium, calci. their meaning in the solar spectrum disappeared at um, iron, bismuth, tellurium, antimony, and meronce.

cury. It must not be supposed, in this or any other It has been found that in the sun's atmosphere case, that other elements might not by a sufficiently there are present the vapors of iron, copper, zinc, laborious scrutiny be proved to exist in the star's atand nickel, besides calcium, magnesium, sodium, mosphere. The observations required, says Mr. and other metals. But the vapors of tin, lead, J Huggins, " are extremely fatiguing to the ere, and silver, and gold, do not appear to be present in the necessarily limited to the stronger lines of each solar atmosphere. One of the most remarkable spectrum." dark lines is due to the presence of hydrogen.

It is clear, however, from the above short list of But it has been found possible to extend these examples, that a considerable variety exists in the researches to the fixed stars. Mr. Huggins and Dr. physical constitution of the fixed stars. This of Miller have done this successfully, and their dis- itself affords a suggestive hint respecting the true coveries afford a means of assigning very sufficient explanation of the variety of color which we have reasons for the colors of the brighter stars. By described. And the peculiarity that in the white analogy also we may extend a similar interpretation stars the hydrogen lines are singularly strong, wbile to the colors of stars not bright enough to give a the metallic lines are as singularly weak, is yet spectrum which can be satisfactorily examined more to the point. Sirius was a red star. Was it

Let us take first the brilliant Sirius. This star at that time unlike present red stars? Does it not belongs to the southern half of the celestial sphere, seem more probable that, if there had existed in and although it becomes visible at certain seasons those days a Huggins or a Miller, and the instruin our latitude, it never rises very high above the ments used so successfully by these observers had borizon. In fact, at its highest, – that is, when been invented, it would have been found that Sirius due south, - it is only twenty-two degrees above did not — when a red star — present peculiarities the horizon, or less than one fourth of the way from now observed only in white stars? the horizon to the point immediately overhead. We recognize, then, the influence of time upon This peculiarity somewhat interferes with the ob- the spectrum of this celebrated star, as probably servation of the star by a method so delicate as that tending to render the lines of hydrogen more disapplied by the celebrated physicists we have named.tinct than of yore, and the lines of the metallic On the other hand the exceeding brilliancy of Sirius elements less distinct. But what is the meaning of ruakes some amends for the effects of atmospheric

such a change? Suppose a chemist, for example, disturbances. By selecting very favorable oppor observing the spectrum of the flame produced by tunities, Huggins and Miller were able to analyze | the combustion of a compound body, should notice the star's spectrum, with the following result:

that the lines of some elements slowly increased in

distinctness, while the lines of others grew fainter, The atrnosphere around Sirius contains sodium, mag. how would he interpret such a phenomenon ? If neslu, hydrogen, and probably iron.

we remembered only that the dark lines are due to The whole spectrum is covered by a very large number of faint and fine lines, indicating a corresponding

the absorptive effect of the vapor they correspond

to, on light which is trying, so to speak, to pass variety in the substances vaporized in the star's atmosphere.

through the vapor, we might readily jump at a cosThe hydragen lines are abnormally strong as com

clusion, and answer that the extent of absorptive pared with the solar spectrum, all the metallic lines vapor is increasing when the lines are growing more being remarkably faint.

| distinct, and vice versa.



But we must also consider that these lines are able for the great number of groups of fine lines in partly the effect of contrast. The line-light held the orange and yellow. before the sun's disc appears black, though so daz- It would seem then that the complementary colors zling when seen alone. It may be, therefore, — or observed in certain double stars, indicate a sort of rather we may say it certainly is the case, — that complementary distribution between the two stars those parts of the spectral streak which seem dark, of elements which in our own sun are associated are in reality luminous; or, — which is merely an- equably and intimately. other way of saying the same thing, - that the va- And we must note here in passing, that it is not pors which absorb light from the solar beams, send absolutely necessary, as some have supposed, that, us light of their own. And so with stars. There- if there are systems of worlds circulating around fore, we have this difficulty to contend against, such double suns, there should be any remarkable that there is no power of determining whether a difference in the quality of light distributed to the change in the intensity of a line, or of a set of lines, planets, as compared with that which we receive is due to a variation in the light-giving power of the from the sun. Sir John Herschel has spoken of corresponding vapor, or to a variation in the quan-1" the charming contrasts and grateful vicissitudes, tity of vapor whose absorptive effects produce the a red or a green day, for instance, alternating with lines.

a white one, or with darkness, according as one or But, inasmuch as it resulted from Mr. Huggins' other, or both of the stars should be above the examination of a temporary star which appeared horizon.” But if the dependent orbs swept in very last year, that the increase of light, — for it was wide circuits about their double sun, they would only the abnormal brilliancy of the star which was receive white light during nearly the whole of each really temporary, — was due to a sudden outburst of their days, since it would only be during a brief of inflamed hydrogen, it seems on the whole more interval that either sun would be visible alone above probable that the incandescent, vapors of stars burn the horizon. with variable brilliancy, than that they vary in Of the deeply colored stars which are visible quantitative distribution.

with the telescope, none have been found suffiAs regards the constant colors of different stars, ciently brilliant to admit of analysis. we are enabled at any rate to deduce negative re- A peculiarity has been remarked by a distin

guished modern observer which is worthy of careful For instance, we may dismiss at once the theory attention. Many of the regularly variable stars, started some years ago by a distinguished astrono- when passing into their phase of minimum brightmer. He supposed that the colors of a star are due ness, exhibit a ruddy tinge which is very conspicuto the proper motions of the star, acting so as — in ous in instruments of adequate power. It does not effect — to lengthen or shorten the waves of light seem easy to explain this as due to any change in proceeding from the star to the earth, just as the the vaporous constitution of a variable star, — since apparent breadth of sea-waves would be greater or it seems difficult to show why such changes should less to a swimmer according as he swam with or occur at regular intervals. It would appear to be against their course. It is quite clear that the more probable that, in general, these changes are effects of a motion rapid enough to produce such a due, either to the rotation of the star itself, and change would be to shift the position of the whole the presentation, in a cyclic order, of the different spectrum, — and this change, though accompanied parts of an unequally illuminated globe, or to the by a change of color, would be readily detected by revolution round the star of an extensive vaporous a reference to the spectral lines.

mass, whose interposition cuts off from us at regular Another theory – that the orange and red tints intervals a portion of the star's light. indicate a lower degree of temperature, must also It is remarkable that a large number of the be dismissed. For we have seen that the spectral known variable stars are red or orange. There is of red stars indicate the presence of the vapor of one notable exception, however, for Algol — the iron and other metals, and nothing but an exceed-celebrated variable in Medusa's head — is a white ingly high temperature could vaporize these.

star. It seems clear that the difference of tint is due to It is probable that a careful examination of the the different arrangement of the dark lines, — in stars with any efficient " color-tester" would lead to other words, to an absolute difference of physical the discovery of many cases of variation in color. constitution. “ There is a striking difference," | Admiral Smyth adopted a chromatic scale of color remarks Huggins, “ between the effect on the color – but a test of this sort is not very satisfactory. of a star of such closely grouped and very dark Opaque colors generally vary with time, so that it lines in the green and blue part of the spectrum of is impossible to say that two observers, even if they Betelgeux, and of the corresponding part of the have used the same strip of colored discs, have realspectrum of Sirius, in which the dark lines are faint, ly made observations fairly comparable inter se. and wholly unequal to produce any noticeable sub-| And it is further to be noted that there are many duing of the blue and green rays."

persons who find a difficulty and uncertainty in the But we have still to consider the peculiarities comparison of stars, or brilliants, with opaque colorpresented by the double stars. We have seen that scales. An ingenious astronomer has suggested the amongst the components of these there are obseryed use of chemical solutions, which can always be resome which present a distinct blue color. It has produced with certainty ; and he has described a been found possible to analyze some of these with method for forming an artificial star in the field of the spectroscope. We have spoken of the charm- view of a telescope, and for gradually varying the ing double star Albireo, the components of which color of the star until it should coincide with that of are orange and blue. Both have been analyzed, - a fixed star whose color we may desire to determine. with this result, that the spectrum of the orange The great objection to the plan is its complexity. component was remarkable for the great strength Colored glasses, through which a small white disc of the lines in the green, blue, and violet, while the within the telescope might be illuminated (just as spectruin of the blue component is equally remark- the wires are illuminated in the ordinary transit tele

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