ing the war, they can be organized, armed, equipped, and concentrated at whatever point military emergency may require. While, therefore, the war expenses have been reduced to the footing of a moderate and economical peace establishment, the national military strength remains unimpaired and in condition to be promptly put forth."

The Military Academy at West Point is now separated from the Engineer Corps, of which it formerly constituted a part. The standard of qualifications for admission has been raised, and appointments to cadetships must hereafter be made a year previous to the date of admission. The report of the Board of Visitors for 1866 shows that the examinations have been creditably conducted, and that the discipline of the Academy is good. The board recommend that the number of cadets be increased from two hundred and ninety-two to four hundred; that the cadets, on graduation, be required to serve at least two years in regiments of the line before entering the Engineer or other staff corps of the Army; and that the standard of qualification be raised by some form of competitive examination. At the last examination the corps of cadets numbered 228, and a class of 40 was graduated.

The act of July 28, 1866, authorized the President, "for the purpose of promoting knowledge of military science among the young men of the United States." to detail officers of experience to act as professors in institutions of learning having upward of 150 male students. It does not appear from the Secretary of War's report that application has yet been made by any college or university for the services of such officers. Provision is also made in the act of July 28th for the instruction of enlisted men at any post, garrison, or permanent camp, in the common English branches of education, and especially in the history of the United States. Another section directs that "a code of regulations for the government of the Army, and of the militia in actual service, which shall embrace all necessary orders and forms of a general character for the performance of all daties incumbent upon officers and men in the military service, including rules for the government of courts-martial," shall be prepared and presented to the Thirty-ninth Congress at its second session.

By direction of the Secretary of War, a board of officers, consisting of Brevet Colonel H. B. Clitz, 6th U. S. Infantry; Brevet Major-General R. B. Ayres, 28th U. S. Infantry; Brevet Colonel H. M. Blach, 7th U. S. Infantry; Captain J. J. Van Horn, 8th U. S. Infantry, Recorder, was assembled at West Point, N. Y., on the 25th of June, for the purpose of recommending such changes in authorized infantry tactics as shall make them simple and complete, or the adoption of any new systein that may be presented to it, if such change be deemed advisable.

The board was to examine and report on

any system of infantry tactics that might be presented to it, and the superintendent of the Military Academy was to give it facilities for testing with the battalion of cadets the value of any system. Besides the system of General Casey, necessarily before the board, two others were presented: one by Brigadier-General Win. H. Morris, late U. S. Volunteers; the other by Brevet Major-General Emory Upton, U. S. Army. The system prepared by General Upton is entirely new, and substitutes wheeling by fours for the facings of other tactics. Among the features that distinguish it from all other systems are, that it simplifies all the movements, and requires less instruction on the part of enlisted men; that it ignores inversions, gives greatly increased mobility to large bodies of troops, doubles the number of ways of passing troops from the order in column to the order in battle, and presents always the front rank in front; that it is equally adapted to wooded and open country; that it presents a new formation for infantry in single rank-a formation eminently adapted to the intelligence of the American soldier, and to breech-loading fire-arms, fast being introduced into all armies; that it enables a skirmish line to be promptly doubled, either for offensive or defensive purposes. The system embraces complete instruction for the soldier, skirmishers, battalion, brigade, division, and corps, and is in one volume, containing about one-half the number of pages in the three volumes of the present system.

General Casey's, or the authorized system, which was before the board, is based upon the French tactics, or is almost literally a copy of them. A modification of this was offered by General Morris; but they reported favorably upon the above system of General Upton, and, by the order of the President, it has become the authorized tactics for the Army and the militia.

ASIA. The progress of the Russians in Central Asia continued without interruption, and another important tract of land in Independent Toorkistan, with the large cities of Tashkend and Khojend, was annexed. The detailed accounts of the Russian operations widely differed, as they were received either from Russian or British sources, but the annexation of the above two cities, with a large territory, seems to be the permanent result of the year 1866. The tribes of Central Asia were again reported to have invoked British aid against Russia. (See RUSSIA.)

In China, rebel movements disturbed the peace of the empire throughout the whole year, and in the latter months the Mohammedan rebels were reported to be in possession of the whole province of Kansuh. Piracy in the Chinese waters continued to make the greatest ravages upon commercial vessels, and the joint operations of the Chinese and British fleets were unable to subdue it. The relations of China to foreign powers remained friendly, and a new port was opened in the northern part of the

empire. In the Corea, a dependency of China, two French bishops and seven priests were massacred-an outrage which led to a French expedition against that country. The Chinese Government repudiated all responsibility for the action of the Coreans, and made no objection to the French expedition. (See CHINA and COREA.)

The relation of Japan to foreigners becomes more and more friendly. The treaties concluded with the chief foreign nations remained in force, and further provisions in favor of foreign commerce were secured by a new treaty concluded between American, English, French, Dutch, and Japanese plenipotentiaries on June 25th. A civil war broke out between the Tycoon and one of the princes, before the termination of which the Tycoon died. (See JAPAN.)

British India remained free from disturbances, the difficulty with Bhootan being fully settled in February. But the country suffered from a terrible famine, which carried off a very large number of people. On the western border of India civil broils continued in Affghanistan throughout the year, and in Farther India a revolution broke out in Burmah, which, however, was unsuccessful. (See INDIA and BURMAH.)

The "Geographical Year-book" of Dr. Brehm for1866 (Geographisches Jahrbuch, Gotha, 1866, pp. 53 to 70) gives the following statements on the area and population of the several territories of Asia:

ASTRONOMICAL PHENOMENA AND PROGRESS. The march of astronomical discovery during the year 1866 has not lagged behind that of the other great departments of science. To chemistry, astronomy is especially indebted; for there is scarcely a discovery made in the domain of the former science which does not, or may not, contribute to the solution of some of the enigmas which still abound in the latter. The spectrum analysis, the original function of which was to determine the presence or absence of the earthy elements in the chemist's laboratory, is now the familiar guest of the astronomer in his watchings through the night, and discloses to him what all his * One geographical square mile equal to 21.21 English

square miles.

improved telescopes had hitherto not availed to show, the constitution of the sun, and the stars, and the comets, and enables him even to hazard a guess at the material nature of the far-away nebula. The application of this new and powerful instrument to astronomical investigation has given rise to many brilliant speculations, which may have to be discarded hereafter, but it has also added many facts to our knowledge of the heavenly bodies. Just in proportion as the spectrum apparatus is improved from year to year-and there can be no doubt that improvements will continue to be made indefinitely in a field of inquiry so prac tical-the burden of mystery which rests upon astronomy will be lifted; and so we may go on from one discovery to another, until the splendid thought uttered by Mr. Grove, in his address at the last annual meeting of the British Association, may be realized. He said: "We, this evening assembled, ephemera that we are, have learned by transmitted labor, to weigh as in a balance other worlds larger and heavier than our own, to know the length of their days and years, to measure their enormous distance from us and from each other, to detect and accurately ascertain the influence they have on the movements of our world and on each other, and to discover the substances of which they are composed. May we not fairly hope that similar methods of research to those which have taught us so much, may give our race further information, until problems relating not only to remote worlds, but possibly to organic and sentient beings which may inhabit them; problems, which it might now seem wildly visionary to enunciate, may be solved by progressive improvements in the modes of applying observation and experiment, induction and deduction?"

The public interest in astronomy has been more than usually stimulated this year by the occurrence of two wonderful phenomena: the sudden apparition and disappearance of a star, perhaps not inferior in size and splendor to our own sun; and the great meteoric shower of November (see METEORS). Events of this kind have a favorable effect upon the science of astronomy, because they tend to popularize it, and to make the great body of the people more willing to contribute the necessary funds for the erection and support of first-class astronomical observatories. It is not improbable that, before many years, every important city in the Union will have an observatory equal to that recently established by the liberality of the citizens of Chicago.

The Temporary or Variable Star in Corona. -The most remarkable astronomical event of the year was the appearance of a temporary or variable star in the constellation of the Crown, less than a degree distant from & Coronæ in a S. E. direction. It was seen at the Washington Observatory on the night of May 12th, when its size was that of a star of the 2d magnitude. Its lustre was a pure soft white. On the fol

lowing night it had apparently sunk from the 2d to the 3d magnitude. On the night of the 14th of May it was studied at the Cambridge Observatory, and was then reported to be of about the 3d magnitude. By the 19th its brilliancy had decreased by nearly two magnitudes, and it was then very near the limit of visibility to the naked eye. On the 20th it was no longer perceptible to the unaided vision, but could easily be seen through an opera-glass. The star had dwindled to the 9th magnitude by the 9th of June. The following was the table of magnitudes as estimated by Mr. B. A. Gould, of Cambridge (American Journal of Science, xlii., 124):

the gas consisted chiefly of hydrogen. Observations were also taken on several successive evenings, during which the continuous spectrum diminished in brightness more rapidly than the gaseous spectrum. Messrs. Huggins and Miller suggest, as their explanation of these brilliant phenomena, that, in consequence of some vast convulsion, larger quantities of gas were evolved from the star, that the hydrogen present was burning in combination with some other elements, and that the flaming gas had heated to vivid incandescence the solid matter of the photosphere. As the hydrogen was consumed, the phenomena would diminish in intensity and the star rapidly wane. The results of the observations of Messrs. Huggins and Miller were confirmed by those of Messrs. Stone and Carpenter, at the Royal Observatory, on the night of May 19th.

Humboldt, in his "Cosmos," gives the following list of temporary stars, which are recorded in history, with variable degrees of certainty as

June 9.

One observer in Philadelphia says that he saw on the 23d of September, 1865, a brilliant star in Corona, not laid down in the maps. It was reported to have been seen in London, Canada West, about May 1st, when its brilliancy was about equal to that of e Coronæ, or between the 3d and 4th degrees of magnitude. It was seen in Ireland and England on the 12th of May, and in France on the 13th. The descriptions of the star given by all the foreign observers at that time agree with those of the various observers in this country. On the 16th of May it was observed and subjected to the spectrum analysis by William Huggins, F. R. S., and W. A. Miller, Prof. of Chemistry in King's College, London, whose applications of that new power to the solution of some astronomical problems have been among the most valuable scientific results of the year. At that time the magnitude of the new star was below the 3d. In the telescope it appeared to be enveloped in a faint nebulous haze, which extended to a considerable distance and faded away at the boundary. A comparative examination of neighboring stars showed that nebularity really existed about it. Its spectrum was unlike that of any other celestial body thus far examined. The light was compound, and had apparently emanated from two sources. The principal spectrum was analogous to that of the sun, evidently formed by the light of an incandescent solid or liquid photosphere, which has suffered absorption by vapors of an envelope cooler than itself. The second spectrum consisted of a few bright lines, indicating that the light by which it was formed was emitted by matter in the state of luminous gas. To the eye the star appeared nearly white; but as it flickered there was seen in occasional preponderance of yellow or blue. The lines of the second spectrum indicated that

The majority of these stars shone with great splendor when first seen. Only three of the known variable stars, according to Humboldt, have been less than the 1st magnitude at the height of their brilliancy. The star of 389 A. D. was for three weeks as bright as Venus, and then rapidly disappeared from view. That of 1572 was seen at mid-day on November 11th, and no longer visible in the following March. It was as bright as Sirius, and reached the lustre of Jupiter. The star of October, 1604, also exhibited great splendor. The stars of 393, 827, 1203, and 1609, are considered one and the same; and a reappearance is predicted in 2014-5. The periods of visibility of these stars differ greatly. That of 389 was three weeks; of 827 four months; and of 1012 three months. Tycho Brahe's star in Cassiopeia (1572) shone for 17 months. Kepler's star in Cygnus was visible 21 years before it totally disappeared. It was seen again (as a star in the same position) in 1655, and was then of the 3d magnitude.

The star of 1866 appears to be identified with No. 2,765 of Argelander's zone + 26° marked

by Argelander as of 9.5 mag. In Wollaston's catalogue (1790) an object is noted upon a place which, reduced to 1866, accords with that of the variable. There is also a nebula marked on Cary's globe, which is near the spot occupied by the new star. This nebula is not on Herschel's catalogue. Sir J. Herschel, on the 9th of June, 1842, marked as visible to the naked eye a star whose place agrees so nearly with that assigned to the new variable, that he cannot help believing it to be the same.

These splendid phenomena have occurred so rarely since the time when scientific apparatus and methods were introduced into astronomical observation, that but little is known of them. The spectrum analysis, this year, has probably thrown more light upon the mystery than all previous investigations.

Eccentricity of the Earth's Orbit, and its Relations to Glacial Epochs.-Mr. James Croll has elaborated an ingenious theory in explanation of the glacial epoch, evidences of which abound on the earth's surface. The theory was originally propounded by Sir John Herschel more than 30 years ago, and may briefly be stated as follows: The mean distance of the earth from the sun being nearly invariable, it would at first be supposed that the mean annual supply of light and heat would also be invariable. Calculations show, however, that this mean annual supply would be inversely proportional to the minor axes of the orbit. This would give less heat when the eccentricity of the earth's orbit is approaching toward, or is at its minimum. Mr. Croll offers reasons for believing that the climate, at least in the circumpolar and temperate zones, would depend on whether the winter of a given region occurred when the earth, at its period of greatest eccentricity, was in aphelion or perihelion. If in its aphelion, then the annual average of temperature would be lower; if in its perihelion, the annual average of temperature would be higher than when the eccentricity was less, or approached more nearly to a circle. He then calculates the difference in the amount of heat at the period of maximum eccentricity to be as 19 to 26, according as winter would take place when the earth was in its aphelion or perihelion. The mean annual heat may be assumed to be the same, whatever the eccentricity of the orbit, and yet if the extremes of heat and cold in winter and summer be greater, a colder climate will prevail; for there will be more ice accumulated in the cold winters than the hot summers can melt. This result will be produced by the vapor (aided by shelter from the rays of the sun) suspended in consequence of aqueous evaporation. Hence glacial periods occurred, when the orbit of the earth was at its greatest eccentricity, on those parts of the earth's surface where it was winter when the earth was in its aphelion; carboniferous or hot periods occurred where it was winter when the earth was in its perihelion; and temperate periods when the eccentricity of the earth's orbit

was at a minimum. All these gradually slide into each other, producing at long-distant periods alternations of cold and heat, some of which are actually observed in geological records.

Mr. Croll has calculated values of the eccentricity, and longitudes of the perihelion, at intervals of 50,000 years for 1,000,000 years past and 1,000,000 years to come, for the purpose of arriving at some better knowledge of these secular changes of climate, proved to result from eccentricity. He has determined the values at epochs of 50,000 years because the eccentricity changes so slowly that it is not necessary to calculate them at shorter intervals. From these the opinion is deduced that the glacial epoch of the geologists began about 240,000 years ago, and extended down to about 80,000 years ago; that the time of the greatest cold was 200,000 to 210,000 years ago; that the next preceding glacial epoch was about 750,000 years ago, still another 950,000 years ago, and that a similar condition of things will take place 800,000, 900,000, and 1,000,000 years to come.

This theory has elicited much discussion and able opposition in the English scientific magazines. It is claimed by those who dissent from it that, admitting the accuracy of Mr. Croll's determination of the values of the eccentricity, such a state of facts alone is not sufficient to account for the glacial epoch known to geologists.

Sun-Spots.-At a meeting of the Royal Astronomical Society, Mr. Huggins presented the result of his observations of bright "granules" on those parts of the sun which are free from spots. These granules are the same appearances which have been called by other observers "willow-leaves," "rice-grains," "shingle-beach," and "bright nodules," all of which terms convey about the same idea of the phenomenon. The granules are distributed over the whole surface of the sun, excepting those areas which contain spots. When observed with powers of only 100 diameters, they present the appearance of rice-grains, but at higher powers, irregular masses may be seen. The granules do not appear to be flat disks, but bodies of considerable thickness. They average about 500 miles in breadth, and 500 or 600 miles in length; some being smaller, and occasionally one appearing of 1,000 or 1,200 miles in diameter. On many parts of the sun they lie in groups, the components being separated by small intervals. These groups vary in form, in some places taking the shape of round or oval cloud-like masses, and are elsewhere long, irregularly formed bands. To these groups, and to the varying brightness of the material between the groups and the granules, is to be attributed the coarse mottling of the sun's surface when observed by low powers. By some theorists they are considered to be recently condensed incandescent clouds, and by others as ridges, waves, or hills, on the surface of comparatively large luminous clouds.

In a recent essay, M. Chacornan expresses the opinion that the sun is a liquid incandescent mass, surrounded by a dense and imperfectly transparent atmosphere. In this atmosphere the solar vapors, raised by evaporation from the liquid nucleus, ascend till acted upon by the cold of the celestial spaces, when they are converted into luminous crystals. He attributes the spots to the engulfment of vast areas of these photospheric crystals, which lose their brightness as they sink. Another observer speaks of "several roundish, isolated portions of luminous matters (having the appearance of icebergs floating in a black sea) in the centre of an umbra."

During the year ending August 1, 1866, 282 negatives of the sun were taken in 158 days by the heliograph at Kew. The areas of the spots. and penumbra were accurately measured, and the heliometric latitude and longitude calculated.

Father Secchi has completed the reduction of magnetic observations made during the years 1859-65, and of sun-spots during the same period. The results show the reciprocal influence of periodic variations of spots and of amplitudes of the daily magnetic oscillations:

It will be observed that the minimum of spots corresponds to the minimum of magnetic variations.

Spectra of some of the Fixed Stars, the Moon, and Planets.—Messrs. Huggins and Miller have I spent much time during the past two and a quarter years studying the spectra of the fixed stars. Very few nights were favorable for observations, owing to the ever-changing want of homogeneity in the earth's atmosphere. The light of bright stars is very feeble when subjected to the large dispersion necessary to give certainty and value to the comparison of the dark lines of stellar spectra with the bright lines of terrestrial matter. For the purpose of these examinations, Messrs. Huggins and Miller nade great improvements in the apparatus employed, bringing it to a point of perfection hitherto unknown. About fifty stars were examined by them, but their principal efforts were concentrated upon three or four of the brightest, the spectra of which are as rich in lines as the sun. The few really fine nights which are available whilst a star is well situated for such observations in respect of altitude and

sun-setting, make the complete investigation of a star the work of some years.

Aldebaran (a Tauri)-a pale-red star-is strong in the orange, red, and green lines. Nine of its spectra are coincident with certain lines in the sun-spectrum, indicating the presence of sodium, magnesium, hydrogen, calcium, iron, bismuth, tellurium, antimony, mercury. No coincidence was observed with nitrogen, cobalt, tin, lead, cadinium, lithium, and barium. Orionis (Betelgeux)-an orange-tinted star-shows strong groups of lines, especially red, green, and blue. The lines are coincident with those of sodium, magnesium, calcium, iron, and bismuth.

a

B Pegasi-of a fine yellow color-reveals the presence of sodium, magnesium, and perhaps barium. The absence of hydrogen lines in this star and also a Orionis, is an observation of considerable interest.

The spectrum of the brilliant white star Sirius is intense, but owing to its low altitude, the observation of the finer lines was rendered difficult by motions of the earth's atmosphere. Sodium, magnesium, hydrogen, and probably iron lines, were found. The hydrogen lines were strong. The white star, a Lyræ, strongly resembles Sirius through the spectroscope. The spectra of Capella, a white star, and Arcturus (red), are analogous to the sun. In the lastnamed star the sodium line was ascertained beyond a doubt. In Pollux, coincidences were remarked with the sodium, magnesium, and probably the iron lines. Sodium lines are discovered in a Cygni and Procyon.

In the moon, no other strong lines are visible than those of the solar spectrum, when the sun has a considerable altitude. The quantity of light from different parts of the moon is very different, but the lines of the spectrum are in every case the same. The result of these examinations is wholly negative as to the existence of any lunar atmosphere.

Lines of orange and red are discovered in the spectrum of Jupiter, which are attributed to the modification of solar light before reaching our atmosphere, and are therefore due probably to absorption by the atmosphere of Jupiter. On one night, the moon and Jupiter being near each other, the opportunity was seized to compare them directly with each other, and these lines were the only perceptible difference observed between the two bodies. Similar bands in the orange and red are seen in Saturn.

In Mars no lines were detected in the red, like those in Jupiter and Saturn, with the exception of two or three strong lines in the extreme red. The spectrum of Venus is of great beauty, corresponding with that of the sun.

Comets.-Comet 1, 1866, was an oval nebulous mass, surrounding a very minute and not very bright nucleus, which possessed no sensible magnitude in the telescope. The light of the coma was different from that of the minute nucleus. The latter was self-luminous,