« VorigeDoorgaan »
an exact photograph of the heavens, and the stars of various magnitudes upon the this not only of stars up to the ninth mag- new gelatine plates :nitude, but those of the eleventh, twelfth,
Exposure. thirteenth, and even fourteenth magnitude;
Minutes. and these lesser magnitudes will not add Magnitude. difficulties further than the exposure of the
0.01 sensitive plate for a longer time.
0.03 Everybody knows that stars beyond the Fourth,
0.1 sixth magnitude are invisible to the naked Fifth.
0.2 eye, and that the term “ magnitude” ap
1.3 plies simply to the apparent brilliancy of
3.0 the stars, those of the first magnitude being Ninth.
8.0 the most brilliant, those of the second a Tenth.
20.0 little less brilliant, and so on, those of the
00. sixth being the last that can be seen with
00. the naked eye. Here is a table showing
00. the probable number of stars of every magnitude up to the fourteenth :
Thus five one thousandths of a second
are sufficient exposure to photograph a star Magnitudes.
of the first magnitude, a half second's First..
exposure takes a picture of the smallest Second.
stars visible to the naked eye, and thirtein Third.
minutes are needed to photograph those Fourth,
of the fourteenth magnitude. A plate Sixth
4,800 24 x 30 centimetres covers five astroSeventh.
nomical degrees. If at a given moment Eighth.
8000 telescopes arranged for photography Ninth.
should be opened all over the earth, and Eleventh
1,000,000 turned upon 8000 points of the sky, all the Twelfth
3,000,000 points being agreed upon in advance, the Thirteenth.
8000 plates would have photographed the Fourteenth.
entire heavens and registered the 40,000,The stars of the fourteenth niagnitude 000 stars of which we spoke above. are visible through the best astronomical Placed side by side in their proper posiinstruments. It will be seen that the total tions, these 8000 plates of five degrees each of these first fourteen magnitudes exceeds would represent the 41,000 astronomical 40,000,000. To try to catalogue this celes- degrees of which the surface of the tial army would be not only a superhuman heavens is composed. task, but absolutely beyond realization This kind of instantaneous photography for errors would creep inevitably into such of the heavens would be ideal, but it would a number of observations, as well as into not be possible because, first, at any given their reductions, tbeir transcriptions, and moment night extends over less than half their places upon a map.
the globe ; and, second, because the atmosYears and years would not suffice, and phere is never perfectly clear ; and, last, while the work was in progress the stars
because these 8000 instrnments would inthemselves would change their positions volve an immense expense, a matter which in space, for each of them is animated by it is simpler and more practicable to reits own motion more or less swift.
duce to a minimum. The work will probNow photography can effect this prop- ably be divided among the following oberly and in the simplest manner, thanks to servatories in proportion to the number of the perfection to which the art and its plates set against each :methods have been brought.
And do you
Number of Plates. know how long it would take to perform Paris,
1,260 this gigantic task, to erect this imperish. Bordeaux,
1,260 able monument of astronomy? In thirteen
1,080 minutes ! Following are figures showing
1,149 with substantial accuracy the duration of Oxford.
1,180 exposure necessary to get an impression of Helsingfors.
Number of Plates. what it did not see before ; at the end of Potsdam...
1,232 an hour it will see better still, and the Rome..
longer it remains directed toward the unCatane.
1,008 San Fernando.
known, the more completely will the eye
1,260 possess it, without fatigue and always betSantiago..
1,260 ter. La Plata,..
And it preserves upon its retinal plate Rio Janeiro.
1,376 all that it has seen. Our eye retains images Cape of Good Hope..
but an instant. Suppose, for example, that Melbourne.
1,149 you kill a man at the moment when,
quietly seated in bis chair, he has his eyes There will be about 22,000 plates of open and directed toward a bright window: two degrees each, arranged so that their (There is nothing improbable in the supborders shall overlap each other sufficiently position upon a planet where all the citito register all the stars without fail and zens are soldiers and kill each other in all thus in time cover the whole heavens. manner of ways at the rate of 1100 daily.) The work will probably be completed in Then suppose that you tear out his eyes five or six years.
(I should have said that the hypothesis Thus nineteenth century science will be- involves dealing with an enemy), and that queath to posterity an invaluable and im- you immerse them in a solution of alum ; perishable statement as to the sidereal these eyes will then retain the image of heavens which in future centuries will the window with its transverse bars and serve as a certain basis for the solution of its light spaces. But in a norinal state of the great problem of the constitution of things our eyes do not retain imagesthe universe.
there would be too many of them, besides. The human eye certainly is an instru. The giant eye of which we speak holds ment admirably adapted to its purpose. fast everything it sees. Its only need is How transparent is this living crystal, how a change of the retina. delightful are its hues, what depth it has !
Yes, the artificial retina sees more what beauty! It is life, passion, light ! quickly and better. And, by virtue of a Close the eyes, and how much of the property wholly lacking in the human eye, world remains ?
it penetrates abysses where we do not and And yet the lens of a photographer's never could see anything. This is, percamera is a new eye that gives the finish- haps, its most astonishing faculty. ing touch to ours, that surpasses it, that Place the eye, for example, at the eyeis more marvellous still.
piece of a telescope whose object-glass This giant eye is endowed with four im. measures thirty centimetres in diameter ; portant advantages as compared with our such an instrument is the best for practical eye : it sees more quickly, further, longer, observations. and, inestimable faculty-it fixes, prints, With this glass of thirty centimetres preserves what it sees.
diameter and three and a half inetres in It sees more quickly : in the half thou- length, we may discover stars to the foursandth part of a second it photographs the teenth magnitude, that is to say, about 40,sun, its spots, its whirlwinds, its fames, 000,000 stars of all kinds. its mountains of fire, in an imperishable Now replace our eye by the photodocument..
graphic retina. Instantly the most brilliant It sees further : turned at darkest night stars beat upon the plate and mark their toward any part of the heavens whatever, likenesses there. Five one thousandths it discovers, in the atoms of the Infinite, of a second suffice for a star of the first stars, worlds, universes, creations that our magnitude, one hundredth for those of the eye could never see by any possibility, no second, three one hundredths for those of matter bow powerful a telescope were the third, and so on, according to the probrought to bear.
portions expressed above. It sees for a longer time : what we can- In less than one second the photographic not contrive to see after several seconds eye has seen all that we could perceive of attention, we can never see.
with the naked eye. eye needs but to look sufficiently long ; at But this is as nothing. Stars visible the end of a half hour it will distinguish only through the telescope also come and
beat upon the plate and thereon inscribe sun lies at such a depth that its light, so their images. Those of the seventh mag- to speak, reaches us no longer. The natnitude take a second and a third to make ural eye of man never would have seen it, their impressions on the plate, those of the and the human mind never would have eighth need three seconds, those of the guessed its existence but for the impleninth eight seconds, those of the eleventh ments of this modern art. And yet this fifty seconds, those of the twelfth require feeble light, come from so far, is sufficient two minutes, those of the thirteenth five to make an impression upon a cheinical minutes, and finally, those of the four- plate which will preserve its picture unteenth thirteen minutes.
alterably. If we have left our plate exposed for a And this star might be of the eighteenth quarter of an hour we shall find photo. or the nineteenth magnitude; and beyond, graphed upon it all the region of the sky so little that the human eye could never see toward which the telescope was directed, it, even aided by the most powerful teleall that this region contains, all that we scopic appliances (for there will always be could have contrived to discover with in. stars beyond our range of vision); and yet finite difficulty by a series of very arduous it will come and hurl its slight ethereal and long-continued observations.
on the chemical plate set up to But we have merely entered upon the await and receive them. marvellous.
Yes, its light will have travelled during Let the photographic eye continue to millions of years. When it started the observe in place of the human eye ; it will earth did not exist, the real earth with its penetrate the unknown. Stars invisible humanity ; there was not a single thinking to us become visible to it. After an ex- creature on our planet ; the genesis of our posure of thirty-three minutes stars of the world was in the process of development ; fifteenth inagnitude will have finished their perhaps only in the primordial seas that task of impressing the chemical retina and enveloped the globe before the uprising of placing there their images.
the first continents, before the primitive, The same instrument which to the human clementary organisms formed themselves eye reveals stars of the fourteenth magni- upon the bosom of the waters, preparing tude and which would register about 40,- slowly the evolutions of future ages. This 000,000 stars in the entire heavens, dis- photographic plate takes us back to the closes to the photographic eye 120,000,- past history of the universe. During the 000, including only those of the fifteenth ethereal flight of this ray which comes toinagnitude. It could reach forth to the day to beat upon the plate, all the history sixteenth and throw before the dazzled ad- of the earth has been accomplished, and miration of the observer a luminous maze in this history that of humankind is but a of 400,000,000 stars.
single wave, an instant. And during this Never before in all the history of man- time the history of the distant sun which kind have we had in hand the power to pen- photographs itself to-day has been accometrate so deeply into the abysses of the In- plished also ; perhaps it became extinct finite. Photography with its recent im- long since, perhaps it is actually out of provements takes a clear picture of every existence. star, no matter what its distance, and sets Thus this new eye which transports us it down in a document that can be studied across the Infinite enables us at the same at leisure. Who knows if some day in time to trace the periods of past eternity. the photographic views of Venus or Mars
Yes, many of these far-away suns that some new method of analysis may not dis- we are taking such pains to photograph no cover to us their inhabitants? And its longer exist. The end of the world has power stretches forth to the Infinite. Be- come to them as it will come to us; and hold a star of the fifteenth or sixteenth, the luminous couriers that they sent us even seventeenth magnitude, a sun like before dying travel forever. our own, separated from us by so great a Astronomy plunges us into the insoluble distance that its light requires thousands, mystery of the Infinite and of Eternity, perhaps millions of years to reach us, not- and therein lies its grandeur.—New Rewithstanding its unheard-of velocity of view. 300,000 kilometres a second ; and this
CHAMBERS'S ENCYCLOPÆDIA. A Dictionary of Aztec Treasure House," “ The Mexican
Universal Knowledge. New Edition. Vol. Guide." New York : D. Appleton & Co. ume VII. Matte-Brun to Pearson, William
Mr. Janvier has made himself an enviable & Robert Chambers, Limiled, London and Edinburgh ; J. B. Lippincott Co., Philadel
name among the short story-writers, specially
in his studies of life among our Spanish-Amer. phia.
ican neighbors. These contributions, origThe seventh volume of Chambers's Cyclo. inally made to magazines and now brought topædia, in its revised form, presents all the evi- gether in book form, are evidently written from dences of thoroughness and excellence which
the results of careful observation of life, cusdistinguish its predecessors. The compact. toms, and types in the very different world ness, accuracy of treatment, and celebrity of which lies across the border of the Rio Grande, the naines which guarantee the authority of Even the casual traveller at once sees the the articles are all that could be desired. change. This difference is accented with the The articles on the more important American finest art and discrimination by our author, topics, including the States and cities of the who also brings to his work a literary skill United States, are copyrighted in this country, which raises him well up to the front among and have been specially prepared for the Lip our minor writers of fiction. Among the pincott Edition, thus giving an increased value stories of special strength are “ San Antonio of to the American issue. Among the articles the Gardens," the opening story ; " Ninita," of noticeable importance as to names and “ The Flower of Death," “ La Mida De Los authorsbip “ Maurice,” by Thomas Padres,” and “St. Mary of the Angels." Mr. Hughes ; " Mecca - Medina,” by Stanley Lane Janvier has a keen sense of the peculiarities Poole ; Mediterranean,'' by Dr. John Mur- which distinguish Spanish womankind from ray ; “ Milton,” by Richard Garnett, LL.D.;
that of the more northerly races, and he emMississippi-Missouri,” by Professor J. P. phasizes and strengthens his situations and Lam berton ; “Mohammed,"
Ema, the differentiation of character on nearly all Deutsch and Rev. John Milne ; Molière," occasions by bringing in the Anglo-Saxon by George Saintsbury ; “Money," by Pro- lover to furnish a keener spice to the value of fessor J. H. Keane ; Mountains," by Pro
the story. fessor James Geikie ; “ Mysteries,” by Rev. S. Baring Gould ; Names,” by Canon THE CANADIAN GUIDE-BOOK, The Tourist Isaac Taylor ; “National Debt,” by Professor and Sportsman's Guide to Eastern Canada J. S. Nicholson ; “John Henry Newman," and Newfoundland. Including full De. by Richard Holt Hutton; “Nihilism," by scriptions of Routes, Cities, Points of InPrince Peter Krapotkine ; “ Painting," by P. terest, Summer Resorts, Fishing Places, G. Hamerton ; Palæography," by Canon etc., in Eastern Ontario, the Muskoga DisIsaac Taylor ; “ Palæontology,” by Professor trict, the St. Lawrence Region, the Lake Jaines Geikie ; “ Palestine," by Walter Besant St. John Country, the Maritime Provinces, and Professor Hull; Parliament," by Prince Edward Island, and Newfoundland. Thomas Raleigh ; and “St. Paul,” by Rev. With an Appendix giving Fish and Game Archdeacon Farrar. It is noticeable that the Laws and Official Lists of Trout and Salmon articles on “Orchard," " Peach,” and “ Pear" Rivers and their Lessees. By Charles G. are prepared by the distinguished novelist, R. D. Roberts, Professor of English Literature D. Blackmore, who, it is rumored, is far more in King's College, Windsor, N. S. With proud of the luscious fruit which he raises in maps and many illustrations. New York : his country home than of the great books which D. Appleton & Co. he has contributed to English fiction. The
Professor Roberts has brought to his work volume is fully worthy of the character which stamps this revised edition of Chambers's something more than the dry ambition of the Cyclopædia as among the leading works of its gazetteer and Grad-Grind compiler. To a very kind in the world.
adequate knowledge of Eastern Canada and
the Maritime Provinces, which are far too litSTORIES OF OLD NEW SPAIN. By Thomas A. tle known to the American tourist, he adds
Janvier, author of “ Color Studies,” “The something of enthusiasm over the history and
legends of his country and a keen sense of lit- the sturdy breed whence he comes ; and erature and its association with people and though he smacks of the soil in his passion for events. The tourist who consults this handy the scenes where his youth has passed, his guide-book will get something more than sug- heart burns with the fire and imagination of "gestions as to routes, hotels, population, in- a poet, which have been fed by some years dustries, etc. Every page is pleasant read- spent at a Scotch university. The young man, ing, and all the arts of the scholar and litté- however, does not fully interpret the utterrateur are brought to bear on the matter in ances of the inner voice till he meets Margaret hand. It has this advantage over the older Ellwood, a young widow, who is down on the guide-books which have been revised year moors sketching. Previous to this time he after year, that it is fresh, and can afford to had obeyed the first flush of fancy by entering give ample space to the casual things that into a tacit engagement with a young girl lend charms to travel. The book is planned connected by marriage with his family. With after the method of Baedeker, like the other Bessie, however, it is the passionate outpour. Appleton Guide Books, the most scientifie ing of her whole simple nature. When Dick and convenient yet devised. It is to be and Mrs. Ellwood come together, the man at hoped that this excellent guide will be fol. once gives his soul into the keeping of a strong lowed by another on Western Canada, that great nature in full sympathy with all his aswonderful region opened up by the Canada pirations ; she, the victim of an unworthy Pacific Railway, the scenic beauties and first marriage, finds in this fresh, true-hearted future possibilities of which excite the ad. and gifted son of the moors a true mate. The miration of all those who have paid any at- problem presented is this : Dick and Margaret tention to the subject.
recognize in each other the certainty of the
highest marriage relation. Yet Dick has given A ROMANCE OF THE MOORS. By Mona Caird.
the innocent country lass the right to love him New York : Henry Holt & Co.
and to marry him according to the ordinary
conventions of worldly honor. The matter, This novelette, we believe, is the first issue as between the three, is discussed with much in the United States under the provisions of pertinence and freshness of suggestion. Bes. the International Copyright Law, but it is not sie gives up Dick, and insists that Margaret the only or the chief reason why it is worth shall marry him. She answers : notice. Mrs. Caird has made herself some- “ What ! after you have set me such an exwhat prominent as an agitator and reformer ample! Not for worlds! We must not im. in respect of the marriage question. Her ad. prison our eagle before he has even spread his vocacy of such legal modifications of mar. wings." riage as will tend to relieve her sex of at least “ But he will not fly always," said Bessie, the most stringent pressure of ill-assorted practically. When he comes back-?'' unions ; her radical views on the subject of “ We can both be ready for him with open divorce, and her insistence that marriage cages, nicely painted, elegant cages, with every should not be binding except when a genuine comfort for a vagrant eagle disposed for a love and harmony exist between husband and quiet life. And then he can enter which he wife, have subjected this lady to rancorous likes, or neither." With this inconsequent criticism. We may naturally expect, then, conclusion the romance ends, and we are led that any povel emanating from her pen will to suppose that Dick goes up to London to touch, if only indirectly, this burning ques. pursue literature, and the two women live to. tion. “A Romance of the Moors” does not gether, devoted to each other and to him, each relate to injudicious marriage consummated, ready with the “ open cage." This is an ideal but it takes up the stress and conflict in the arrangement for the lucky Dick, but we fancy hearts of three people, two women and one most hardened novel-readers among woman. man, as to the rights of love and the consider- kind will set up a vigorous protest. Whatever ations leading to marriage. The story is very we may conclude about the dubious climax, simple, a mere idyl, but in it is set a burning Mrs. Caird has written a fresh and racy story, issue, told with much vigor and directness with plenty in it to set people thinking, and, of purpose. Dick Coverdale, the son of a after all, that is the principal use of a book, well-to-do Yorkshire farmer, is totally unlike whether a novel or otherwise.