Popular Science Monthly/Volume 36/February 1890/Sketch of James Glaisher, F.R.S.

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James Glaisher.


SKETCH OF JAMES GLAISHER, F.R.S.

METEOROLOGY owes to Mr. Glaisher the results of many years of patient labor at the institutions and observatories with which he has been connected; a series of valuable researches undertaken at the instance of the British Association; and those daring and brilliant observations in a balloon at very great heights in the atmosphere with which his name is most conspicuously associated. Yet, as has been observed by one of his biographers, "his numerous contributions to scientific and popular literature, often published in a most unobtrusive manner, which is very characteristic of the man, have scarcely gained him so wide a reputation in the learned world as he certainly deserved."

James Glaisher was born, according to the "Men of the Time," in London in 1809. In 1829, as assistant in the principal triangulation of the ordnance survey in Ireland, he was charged with the meteorological observations on the Bencorr and Keeper Mountains. These observations were published in 1836. From 1833 to 1836 he was assistant at the Madingly Observatory, near Cambridge; was appointed in the latter year assistant in the astronomical department of the Greenwich Observatory; and was made in 1840 Superintendent of the Magnetical and Meteorological Departments of the same institution, where he remained till he retired from the public service at the end of 1874. In 1865, upon the death of Admiral Fitzroy, he was appointed to the control of the meteorological department of the Board of Trade. From 1841 till very recently he has contributed to the registrar-general's reports the quarterly and annual meteorological reports embodying the results of the reductions and discussions of the observations of about sixty voluntary observers scattered over England.

Among Mr. Glaisher's earlier contributions to the literature of meteorology were the "Hygrometrical Tables," first published in 1845, which has passed through six editions, and is regarded as a fundamental work in connection with the science; "A Memoir on the Radiation of Heat from Various Substances," 1848; certain papers on the forms of snow-crystals, 1855; a report on the "Meteorology of London during the Cholera Epidemic of 1853-'54," published by the Board of Health in 1855; and a report on the "Meteorology of India in Relation to the Health of the Troops," 1863, which formed an appendix to the report of a Royal Commission on the Army in India. In 1857 he conducted the experiments and wrote the report of the Royal Commission on the Warming and Ventilation of Dwellings. He was the founder of the Royal Meteorological Society, of which he was the secretary for nearly twenty years, and the president in 1867-'68. He is a past President of the Royal Microscopical Society.

As a member of the British Association he has been active in the meteorological researches undertaken under the direction of that body; and we find his name attached year after year to the reports on "Luminous Meteors," "Rainfall," "Rate of Increase of Underground Temperature downward," "Circulation of Underground Waters as related to the Water-Supply of certain Towns and Districts," and "Mathematical Tables." The reports on "Luminous Meteors" were particularly minute and exhaustive. They seem to have been intended to include as full and accurate accounts as it was possible to get of every meteor that fell anywhere on the earth within the view of a man intelligent enough to describe it; and they embody frequent suggestions as to the direction which future research might take. Thus, the report of 1874 noticed the apparent connection between some meteor-showers and certain comets, and spoke of the coincidences as being numerous enough, and sufficiently exact to render desirable the further cultivation of cometary astronomy by star-shower observations. The report of 1875 pointed out that the work of properly treating meteor observations had become so great as to be beyond the power of the Association to grapple with it, and commended the arrangements which M. Leverrier was making for that study. In 1878 the committee, finding it probable that the highest attainable accuracy in mapping the observed directions of the apparent paths of shooting-stars was the real key to the solution of the problem presented by their nightly flights, and that the question of the possible connection of fire-balls and aërolites, or large stony masses, with such showers—and accordingly, it might be, in certain cases, with comets—depended for its solution on accurate observations of these meteors, recommended the study as an attractive one, and gave a series of directions for following it up.

A committee was appointed at the Aberdeen meeting of the British Association in 1859 to make observations, by means of a balloon, in the higher regions of the atmosphere. Nothing was done for two years, for want of a balloon and an observer. The committee was reappointed at the Manchester meeting in 1861; a balloon was contracted for with Mr. Coxwell, an expert aëronaut, and Mr. Glaisher, the most active member of the committee, volunteered to go up with him and make the observations. Twenty-eight ascents were made from Wolverhampton, the Crystal Palace, and other places not far from London, between the 17th of July, 1862, and the 26th of May, 1866, of which seven were made into extraordinarily high regions, from 22,884 feet to 37,000 feet, or seven miles. In all these ascents, Mr. Glaisher remarks, in the introduction to "Travels in the Air," "I used the balloon as I found it. The desire which influenced me was to ascend to the higher regions and travel by its means in furtherance of a better knowledge of atmospheric phenomena; neither its management nor its improvement formed a part of my plan."

The first ascent was marked by meeting a warm current at a great elevation. Clouds were entered at 4,000 feet, which proved to be also 4,000 feet thick. The temperature at starting being 59° Fahr., fell to 45° at 4,000 feet, and to 26° at 10,000 feet, from which it remained stationary up to 13,000 feet. Then it rose to 31° at 15,500 feet, and 42° at 19,500 feet, after which it fell rapidly to 16° at 26,000 feet.

In the ascent of September 1, 1862, the curious phenomenon was observed of the formation of clouds along the course of the Thames from the Nore to Richmond. The clouds followed the river in its course through all its windings, not departing from it on either side. It being about the time of high water, the formation was supposed to be the effect of the warm current coming np from the sea.

On the 5th of September, 1862, the aëronauts reached the height, which has never been surpassed by man, of 37,000 feet, or seven miles. Mr. Glaisher thus described his experiences after making his observations at 29,000 feet: "Shortly afterward, I laid my arm upon the table, possessed of its full vigor, and, on being desirous of using it, I found it powerless—it must have lost its power momentarily. I tried to move the other arm, and found it powerless also. I then tried to shake myself, and succeeded in shaking my body. I seemed to have no limbs. I then looked at the barometer, and while doing so my head fell over my left shoulder. I struggled and shook my body again, but could not move my arms. I got my head upright, but for an instant only, when it fell on my right shoulder, and then I fell backward, my back resting against the side of the car and my head on its edge; in this position my eyes were directed toward Mr. Coxwell in the ring. When I shook my body I seemed to have full power over the muscles of the back, and considerable power over those of the neck, but none over either my arms or my legs; now, in fact, I seemed to have none. As in the case of the arms, all muscular power was lost in an instant from my back and neck. I dimly saw Mr. Coxwell in the ring, and endeavored to speak, but could not; when, in an instant, intense black darkness came; the optic nerve finally lost power suddenly. I was still conscious, with as active a brain as at the present moment while writing this. I thought I had been seized with asphyxia, and that I should experience no more, as death would come unless we speedily descended; other thoughts were entering my mind, when I suddenly become unconscious as in going to sleep. I can not tell anything of the sense of hearing; the perfect stillness and silence of the regions six miles from the earth (and at this time we were between six and seven miles high) is such that no sound reaches the ear." During this time Mr. Coxwell was in the ring above the car, trying to open the valve. He also lost the use of his hands, and was obliged to seize the cord with his teeth and pull it by dipping his head. Consciousness returned gradually to Mr. Glaisher, and no inconvenience followed the insensibility; and when the party had landed, no conveyance being available, they were obliged to walk several miles.

In the ascent of June 26, 1863, the party passed through layer above layer of clouds to the height of four miles; in the descent, they passed through a fall of rain, and below it a snow-storm, the flakes of which were composed of spiculæ of ice and innumerable snow-crystals. On reaching the ground the atmosphere was thick, misty, and murky, and the afternoon cold, raw, and disagreeable for a summer's day.

The observations made during night ascensions, or those which were continued into the night, on temperatures at different heights, gave results different from the theories previously held on the subject. An increase of the temperature with the height was noticed after sunset. The rate of decline of temperature with elevation when near the earth was subject to variation as the sky was clear or cloudy. From an elevation of three miles cirrus clouds were seen apparently as far above the observers as they seem when viewed from the earth, and that under such conditions that it was hard to believe that their presence was due to moisture. The audibility of sounds from the earth depended considerably on the amount of moisture in the air. The noise of a railway train could be heard in clouds at four miles high, but not when the clouds were far below. The discharge of a gun was heard at 10,000 feet; the barking of a dog at two miles; but the shouting of a multitude at not more than 4,000 feet. Many differences in the results of observations were supposed to depend upon atmospheric conditions, while these vary with the time of day and the season of the year; so that a great many observations would be required to determine the true laws. Having followed up one of the observations recorded above with a captive balloon and by other means, Mr. Glaisher declared to the Meteorological Society, in 1870, that the theory that the temperature is always lower at higher elevations is not true.

Some noteworthy mental impressions are recorded in Mr. Glaisher's descriptions of his ascents. Writing of his feelings at the height of 23,000 feet, and under the imminent necessity of descending at once, he was surprised "at the extraordinary power which a situation like this calls forth, when it is felt that a few moments only can be devoted to noting down all appearances and all circumstances at these extreme positions; and if not so rapidly gleaned they are lost forever. In such situations every appearance of the most trivial kind is noticed: the eye seems to become keener, the brain more active, and every sense increased in power to meet the necessities of the case; and afterward, when time has elapsed, it is wonderful how distinctly at any moment scenes so witnessed can be recalled and made to reappear mentally in all their details so vividly that, had I the power of the painter, I could reproduce them visibly to the eye upon the canvas." A fine description, of which we can quote only a part, is given of the scenery of the upper air: "Above the clouds the balloon occupies the center of a vast, hollow sphere, the lower portion of which is generally cut off by a horizontal plane. This section is in appearance a vast continent, often without intervals or breaks, and separating us completely from the earth. No isolated clouds hover above this plane. We seem to be citizens of the sky, separated from the earth by a barrier which seems impassable. We are free from all apprehension such as may exist when nothing separates us from the earth. We can suppose the laws of gravitation are for a time suspended, and, in the upper world to which we seem now to belong, the silence and quiet are so intense that peace and calm seem to reign alone." The descriptions of sky and cloud scenes that follow are very picturesque.

Mr. Glaisher was elected a Fellow of the Royal Society in 1849. On the death of Lord Chief-Baron Sir F. Pollock, about 1870, he became the third President of the Photographic Society of Great Britain, an office which he still holds. This society presented to him in 1887 a marble bust of himself, executed under its direction by the sculptor Albert Toft. He was a juror in the class of scientific and philosophical instruments at the Great Exhibitions of 1851 and 1863, and was the reporter of the class in 1851.

Mr. Glaisher is the author of more than one hundred books and papers relating to astronomy, meteorology, and the theory of numbers. Some of these have already been mentioned. Among the others are many papers in the "Proceedings of the British Association" relating to his balloon ascensions and the subjects of his special investigations. His best-known work is "Travels in the Air," of which he is joint author, which is composed of the narratives by himself of his own balloon voyages and observations, and accounts by M. Gaston Tissandier and M. de Fonvielle of their experiments in the same line. He edited and compressed the English version of Camille Flammarion's "Atmosphere," performing, in addition to the regular labor of such a task, that of reducing the notations of the French system to their equivalents in English units, and replacing French observations and data with English corresponding ones. In 1877 he translated and edited Amedée Guillemin's "World of Comets." After he retired from the Royal Observatory he devoted himself to the completion of the factor tables, begun by Burckhardt in 1814 and continued by Dace in 1862-'65; Burckhardt published the first three millions, and Dace the seventh, eighth, and ninth millions. The three intervening millions have been calculated by Mr. Glaisher and published, with a full enumeration relating to the whole nine millions, in three quarto volumes. Since 1880 Mr. Glaisher has been chairman of the Executive Committee of the Palestine Exploration Fund.