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triangle. The northern of the two smaller stars is Epsilon Lyræ, a quadruple star. Mr. Burnham and a few other sharp-sighted people can see with the naked eyes that it is a double star, which with the help of an opera-glass almost anybody can do. Through a good telescope each of these doubles becomes itself a double, making four stars in the group- a beautiful sight to look upon. Astronomers, however, take little interest in such a star as this, because it is what they call a wide double," and is so easily seen. What they are interested in are "close doubles," which are generally found to

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OBSERVED POSITIONS OF THE COMPONENTS OF THE DOUBLE known to astronomers, and many of them have

STAR B DELPHINI, PERIOD 26 YEARS.

have physical relations; that is, the smaller star revolves round the larger one as the planets go round the sun in our solar system. The closer the doubles the more likely they are to be physically related. The distance between the two pairs in Epsilon Lyræ is 3 minutes 27 seconds of arc, or 207 seconds, whereas in the 1000 new doubles discovered by Mr. Burnham 743 of them are, on an average, only 15 seconds apart, or 131 times as close as in Epsilon Lyre, while many do not exceed one-fifth of that distance. Such close doubles as some of these not one person in a thousand would be likely to see, even if he looked through the best and largest telescope.

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One of the most interesting double stars is Sirius, or the Dog Star, the brightest star in the heavens. During the winter months one

may see Sirius in the southern sky, south and east of the beautiful constellation Orion, which everybody knows. In the course of some observations of this star the illustrious Bessel, one of the greatest astronomers of the century, suspected the existence of a satellite, the mass of which, acting on the central star, produced certain variations in its movements that had long excited the curiosity of observers. Of this satellite nothing was known, and Bessel's suggestion provoked search for it. Other astronomers studied on the same problem, and one of them, M. Peters, calculated for the orbit of the unknown companion a period of fifty years. Several European astronomers looked for it and could not find it. Such was the state of things until the 31st of January, 1862, when Mr. Alvan G. Clark, one of the makers of the unfinished Chicago telescope then at Cambridge, set it up rudely in the yard of his factory, and turning it upon Sirius discovered the companion which Bessel had foretold and whose position M. Peters had so nicely calculated. Although very difficult to see, being almost in the blaze of the bright star, this satellite or companion has been watched and measured very carefully ever since, and during the twenty-two years that have elapsed it has made a circuit of nearly one hundred and fifty degrees round the large star, and is likely to make a complete revolution in about the time predicted by the French astronomer. For making this discovery the French Academy gave Mr. Clark the Lalande gold medal. The shortest period of revolution now known among double stars is eleven years, and the star is Delta Equulei, the distance of its companion being only two-tenths of one second.

Mr. Burnham's discoveries attracted much attention in Europe because the double stars he discovered were the closest and most difficult

since been found to be in rapid motion like the companion of Sirius. To them it seemed amazing that such difficult doubles could have been discovered by a self-instructed amateur using so small an instrument as one of six inches aperture.

The result was that by this time Mr. Burnham's name was well known abroad, and he himself was in correspondence with many of the leading astronomers of Europe. Two years later M. Angot, one of the French astronomers sent to the islands of the Pacific Ocean to observe the transit of Venus, returned through the United States, under instructions from his government to visit and report on the appliances and work of American observatories. One of the places which he visited was Chicago, and the person in whom he was most interested was our amateur astronomer on Vin

cennes Avenue. In Mr. Burnham's little observatory M. Angot was greatly interested, and said he had never seen one where such important results had been accomplished with such simple and inexpensive appliances. He found no sidereal clock, no transit instrument nothing, in short, but a six-inch telescope mounted equatorially on a stout piece of timber sunk in the ground. The telescope was even without the usual clockwork to keep its motion in correspondence with the rotation of the earth. For this, of course, Mr. Burnham had a substitute, and a very ingenious one too, as M. Angot's description of it will show. It was simply a long, vertical tube filled with sand, with an orifice at the bottom through which the sand could escape, after the manner of an old-fashioned hour-glass. A lead plunger following the descent of the sand through the tube gave the proper motion to the telescope, and held it as firmly on a star as could be done by clockwork. He describes also Mr. Burnham's ingenious mode of construction and reading off his circles, by which much saving of time is secured. The discoveries and work done with this little telescope tested at the time the sight of the best observers in Europe and the resources of much larger and better equipped instruments. Otto Struve, the distinguished Russian astronomer, in a letter addressed to Mr. Burnham in 1876 said he had devoted forty years of his life to the zealous observation and study of double stars. "But when," he went on to say, "I think of what you have done in so short a time, I am almost ashamed of my own labors." How great these labors of Struve were may be judged from Mr. Burnham's own words, as given in his "Double Star Observations," in the "Memoirs of the Royal Astronomical Society," Vol. XLIV.: "Omit the observations [meaning measures, not discoveries] of Dembowski and Otto Struve and our knowledge of nine-tenths of the double stars would not be materially advanced in the last thirty years." This was written in 1879, and Mr. Burnham's own measures and discoveries since would render the insertion of his own name necessary to preserve at the present time the truth of the statement.

As soon as Mr. Burnham was allowed access to the great 18%1⁄2 inch telescope of the Dearborn Observatory, he applied himself to the measurement of double stars, and became as noted an expert in this difficult work as Baron Dembowski or Otto Struve, as his publications in the "Memoirs of the Royal Astronomical Society "sufficiently attest. He never having had instruction from any practical astronomer, his methods of work were original and showed great ingenuity and inventive genius. The form of the micrometer in VOL. XXXVIII.-40.

general use not suiting him, he invented one which has been almost universally adopted, and which the Clarks now attach to all their best telescopes.

In 1877 M. Flammarion of Paris, France, sent to Mr. Burnham a mass of printed proofs and a letter, stating that he had completed and had put in type his " Catalogue of Double Stars which had shown Orbital or other Motion." "But," he continued, "before I publish it I beg to submit the proofs to you for correction and revision-you, whom the scientific world now places at the head of this department of sidereal astronomy." The proofs were corrected and a large number of new measures and new systems in motion were added, which called forth enthusiastic acknowledgments and compliments from the great French astronomer. These facts are mentioned to show in what estimation this man, of whom his own countrymen now know so little, was held by the greatest of European astronomers so far back as 1877. Not only this, but besides his election as Fellow of the Royal Astronomical Society of England he has been made a member of the German Astronomical Society and has received from Yale University the honorary degree of M. A. When a dispute in astronomy involving acuteness of vision has arisen in Europe, which could be determined only by a series of the closest and most delicate observations, Mr. R. A. Proctor has repeatedly called in Mr. Burnham as umpire, and his modest statement has always settled the question.

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At the date of which we are writing, 1876 and 1877, Mr. Burnham had been for four years a regular contributor to "Monthly Notices of the Royal Astronomical Society" of London, "Astronomische Nachrichten of Germany, and other European journals, and had published nine catalogues, embracing nearly five hundred of his own new double stars. When at this time it was suggested to give him the use of the great telescope in the Dearborn Observatory—absolutely unused till thenthe president of the Chicago Astronomical Society asked, "Who is Mr. Burnham?" On September 20, 1876, however, he was appointed acting director of the observatory, which honorary position he held until April 11, 1877, when, through local personal jealousies into which we need not enter, this order was rescinded, the doors of the observatory were closed upon him, the locks even were changed, and he returned to his back yard and his "cheese-box." It was too late, however, to consign such a man to obscurity. His name had begun to be known in this country, and a war-cry was sounded in the leading daily papers of New York, Boston, Cincinnati, and

Chicago; the "American Journal of Science," at New Haven, took up the matter, and in a short time the directors of the observatory were very glad to stop these indignant protests and restore to Mr. Burnham the use of the great equatorial. Since then, happy in the cordial and active coöperation of the present genial director, Professor George W. Hough, he has gone steadily on with his observations, until his friends can say he has discovered more double stars, over one thousand,- and measured them, than any other man, living or dead. To Volume XLIV. of the "Memoirs of the Royal Astronomical Society" he contributed 167 quarto pages of double-star observations, taken during 1877-78, and comprising his tenth catalogue, of 251 new double stars, with measures, and micrometrical measures of 500 double stars. In Volume XLVII. of the same great work (1882-83) will be found 160 more pages of similar observations made by him, comprising his thirteenth catalogue, of 151 new double stars, with measures, and micrometrical measures of 707 double stars. But his great work is yet to be published a complete catalogue of all the double stars ever discovered, with their right ascension and declination, the names of the several discoverers, and all the measures taken by them. This all-important work and tabulated record of all that is known of double stars the United States Government, through the Naval Observatory at Washington, undertook to publish some years ago; but in the press of its regular publications gave up the task after printing some fifty or sixty pages. It is a matter for satisfaction, however, to learn that in all probability the Smithsonian Institution at Washington will complete the work, in which case Mr. Burnham will bring his catalogue down to the date of publication.

This immense catalogue in manuscript, which the author has made for his own use, has greatly contributed to his own success in this department of astronomy. It is the only work of the kind ever made, and double-star observers all over the world send to Mr. Burnham to have their observations verified and to ascertain whether the stars are new. The research and literary labor spent upon it have been simply enormous. His astronomical library of some two thousand volumes contains nearly every star catalogue which has been printed, and the works of every observer in this specialty, some of them in manuscript. Though not in the possession of large means, he buys every book he needs to make his catalogue complete. The rapidity and facility with which he does his literary work are as marked as that with which he uses the telescope.

In 1879 the trustees of the Lick Observatory in California selected Mount Hamilton, situ

ated about seventy-five miles south-east of San Francisco, as the site of the observatory, and wrote to Professor Simon Newcomb of the Naval Observatory in Washington requesting him to make a series of observations on Mount Hamilton for the purpose of testing the atmospheric and other conditions of the locality for an observatory. Professor Newcomb replied that the most competent person in the country for making this examination was Mr. Burnham of Chicago, and recommended him for that duty. Mr. Burnham accepted the appointment and took his six-inch telescope, made by the Clarks, with him to California, and resided on Mount Hamilton for six weeks and made the observations needed. His full and interesting report on the subject was printed by the trustees in 1880. In October, 1881, with Professor Holden, he went out to Mount Hamilton again, by request of the trustees, to observe the transit of Mercury. On both of these occasions he discovered a large number of double stars, chiefly in the southern sky, which at northern observatories are too low to be well seen.

In connection with the observation of double stars it may be remarked that the extreme acuteness of vision which enables one to prosecute such research with the highest success is a very rare gift; and the discovery of close doubles is its severest test. To measure a star- that is, to ascertain by means of the micrometer the distance and position angle of the companion with reference to the principal star- is one thing, and to find new and close doubles is a very different thing. Baron Dembowski, the most noted measurer of double stars, who received for this work the highest gold medal from the Royal Astronomical Society of London in 1879, had no success as a discoverer, and confessed his inability to find new doubles. When, however, a new double had been found by another observer, and the distance and position angle of the companion approximately estimated, he could readily find and accurately measure it. When Mr. Asaph Hall, in 1877, had found the two satellites of Mars and described their positions, it was not difficult for any astronomer who had access to a large Clark telescope to find them and see all that Mr. Hall had seen. The whole difficulty was in seeing them for the first time. Besides the ability to see a difficult object, there is required an intelligence and an experimental knowledge of the subject, which are as rare as the visual faculty itself. Some of the lower orders of animals have more acute vision than human beings; but they do not know all they see, or understand relations to other facts. They have plenty of sight, but are lacking insight. Mr. Burnham's extraordinary powers in both these respects have made him the most

successful discoverer of close.double stars who ever lived.

The five great names in this department of astronomy are the two Herschels, Sir William and Sir John (father and son), the two Struves, Wilhelm and Otto (father and son again), and S. W. Burnham. In science a double star always retains the name of its discoverer and his catalogue number; and, for brevity, a Greek letter is used to express his name, or, in the case of the younger Herschel and the younger Struve, two Greek letters. The Greek letter Beta is the designation of Burnham. In a star list, "B 999" means Burnham's double star, numbered 999 in his catalogue; "318," Wilhelm Struve's star, number 318; and "02 413," Otto Struve's star, number 413. Each star is described in the catalogues of their discoverers by right ascension, declination, magnitude, position angle, and distance, so that no astronomer in the future can lay claim to it. Mr. Burnham knows his thousand stars by name,—that is, by number,— and can speak of the peculiarities of each without referring to his catalogue.

The known doubles are regularly and carefully observed by many astronomers, and their measures, each with a recorded date, will after a time show whether the supposed companion has physical relations with the principal star. If there be no change in the position angle or distance, they are strangers to each other. If there be a change, the rate of orbital motion may be estimated when enough measures are collected. It is possible that two or more stars very distant from each other may fall in nearly the same line of sight, and have the appearance of a double or a triple star. In case, however, of very close doubles, the chance of such a coincidence — one in many thousands—is so remote that there is almost a certainty that such doubles have physical relations and belong to the same system. Measures extending over a series of years will determine the fact. Perhaps our readers may wish to know some

thing of the personal characteristics of our amateur astronomer, and would inquire whether such incessant day and night work affects unfavorably his health and social habits. Does it make him a recluse ? Is he a martyr to science? Has he time for social intercourse, and a taste for any of the recreations and amusements which interest other persons? In reply it may be said briefly that few persons have such uniformly good and robust health as he; few love better the social intercourse of their friends, or are more sportive and entertaining in their conversation. Few play so many games, or play them so rapidly and so well as he. He carries with him no indications of a recluse or a martyr. Why should he?-for his scientific pursuits come within the scope of his amusements. With strangers he has but little conversation, and rather avoids making new acquaintances. He never speaks of astronomy except the subject be introduced by others, and he never poses as a scientific man. Hence persons who have known him intimately for years have never suspected that he was anything more than a bright, agreeable companion, and a good shorthand reporter. He loves nature; and nothing delights him more than to tramp and camp for weeks in the woods of Michigan, around Lake Superior, or among the Rocky Mountains, with a few genial friends, his trusty rifle,- for he is a noted rifle-shot,— and his photographic outfit. In the matter of instantaneous photography he has few rivals, and with his portable camera he has traveled through Europe shooting pictures from steamboats and railroad trains. A competitive prize was offered in England for the best instantaneous photograph. In a spirit of fun he sent some pictures, and a first prize was awarded him. The subject was a cat in the act of springing upon a bird. In late years he has studied photography in its application to astronomy. Few men have a more interesting family, a happier temperament, or get more enjoyment from life than our Amateur Astronomer.

John Fraser.

[SINCE writing the above, Professor Fraser has died. The article has been revised for the press by a friend of the author, who coöperated with him in the preparation of the original paper.- EDITOR. ]

MEMORANDA ON THE CIVIL WAR.

The Canal at Island No. 10.

A REPLY FROM GENERAL SCHUYLER HAMILTON.

To the EDITOR OF THE CENTURY MAGAZINE.

IR: THE CENTURY MAGAZINE for February, 1889, SIRE contains a letter from Colonel George A. Williams, United States Army, speaking quite dogmatically of the origin of the canal above New Madrid which led to the capture of Island No. 10, and rather contemptuously of the honor of suggesting the canal. Colonel Williams alleges the "correct history" to be that the canal was suggested by a saw-mill refugee named

Morrison, who was taken from a raft.

I regret that I was not afforded a hearing upon this subject before Colonel Williams's letter appeared.

Its publication forces me to say that I never saw nor heard of the raft refugee Morrison, mentioned by Colonel Williams, and that the suggestion for a canal which I made to General Pope was original with me. I did not receive the idea, directly or indirectly, wholly or partly, from Colonel Williams, saw-mill Morrison, or from any one else.

As part of the history of the canal incident, I beg space for the following extract from a letter written by me to B. J. Lossing, Esq., on the 7th of June, 1863:

The following record of a conversation of Mr. Solomon Sturgis of Chicago, who contributed very liberally to the equipment of the Sturgis rifles, I find in one of my letters dated March 31, 1862. It may not be uninteresting in this connection. It was said to be characteristic. He said, addressing General Pope : "General Pope, who suggested that plan? Tell the truth, the whole truth, and nothing but the truth; do not rob any man of the credit due him." General Pope replied with a smile, "General Hamilton suggested it, sir." Turning to me, he said, General Hamilton, was it honestly your own conception? Did no one hint it to you - no private, no corporal, no sergeant, no one?" On my replying, "No one, sir," he said: "Sir, give me both your hands, I honor you for it; and, General Pope," said he, " you deserve high honor for adopting so wise a suggestion." That is the record as I made it at the time, and it is true.

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Schuyler Hamilton, Late Maj.-Gen'l Vols., U. S. Army.

NEW YORK CITY, March 31, 1889. [Colonel Williams died at Newburg, N. Y., April 2, 1889.EDITOR.]

An Early Suggestion to Arm Negroes for the
Confederacy.1

AS THERE has been a variety of opinion in relation to the status of negro slaves under the late Confederate States Government during the civil war, I transmit for your consideration, from an official letter-book, a copy of my official letter to Hon. C. W. Harper, chairman of a sub-committee of the Mississippi legislature, then in session at Jackson, Miss., expressing in brief my views as to the employment of slaves in the construction of the military defenses of the State. It is per1 See also the correspondence on this topic between General R. E. Lee and the Hon. Andrew Hunter printed in THE CENTURY for August, 1888. The present article was written before that correspondence appeared.- EDITOR.

haps expedient to note that in the construction of the defenses at Port Hudson, which I had established during the month of August, soon after the battle of laborers for the prosecution of the work; and to reBaton Rouge, I found it necessary to impress slave pair the defenses at Vicksburg, and in some measure extend them, I found it necessary to impress several hundred negro slaves.

It was then a critical period with owners of slaves

along the Mississippi River border, particularly above Vicksburg, where they were constantly menaced by predatory gunboats carrying off slaves, cotton, and supplies, without effective resistance. Under these cir

cumstances, in my preliminary orders it was necessary to restrict, or limit, the field for impressment to the manifested by planters, especially as this public service Mississippi border, to which little or no opposition was was supposed to give some degree of protection to their individual interests.

In connection with the practical operation of this policy the legislative committee requested explicit official information as to my views on this subject, a summary of which I embodied in a letter as follows:

HEADQUARTERS FIRST DISTRICT, DEPARTMENT MISS. & EAST LOUISIANA, JACKSON, Dec. 16, 1862.

To Hon. C. W. Harper. requesting information as to the number of slaves who SIR: In reply to your communication of the 14th inst., might be advantageously used in connection with our military defenses in this State, will say that my own views on the subject go very much beyond what is thought to be politic by most gentlemen, but will in response confine myself within such limits of seeming propriety as may commend the subject to the good common sense of those who are to be affected by it.

At this time, and until they shall be completed, one thousand negro men can and ought to be employed constantly on each of the works at Vicksburg, Port Hudson, and Columbus, and two thousand more could be used in the supply and transportation departments; perhaps a thousand more— part women could be employed for hospital purposes.

Our railroads are in great need of repairs; a thousand negro laborers should be put upon them immediately and continuously employed. The construction and repairs of rolling stock, too, need much attention, and half the negro carpenters and blacksmiths in the State might be well employed upon it, and in the erection of buildings needed for many purposes.

In this way, and by the employment of other servants as teamsters, laborers, cooks, nurses, watchmen, etc.. with our armies in the field, the fighting strength of these armies might certainly be increased one-tenth, and although laborers in the field of the husbandman are as necessary as soldiers in the army, to enable them to prosecute the war waged against us, I yet believe that ten thousand negroes might be spared from the former service in this State, without danger of too great reduction in agricultural supplies, and made almost if not quite as useful in the army and other public service as an equal number of white men. As a system, I think it would be well to introduce into the service, as cooks, one negro for every ten soldiers. These servants, when the troops were absent from camp, could be made available as watchmen for camp and police duty, thus relieving so many soldiers for service in the field.

Negroes thus employed should be organized in detachments and placed under the direction and control of per

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