The Story of Eclipses

by George F. Chambers

The eclipse of May 17, 1882, yielded several interesting and important features although the totality was short—only about 1¼ minutes. Here again favourable local circumstances helped astronomers in more ways than one. It was in Egypt that the eclipse was visible, and Egypt is a country which it is exceedingly easy for travellers to reach, and it is also noted for its clear skies. These were doubtless two of the reasons which combined to inspire the elaborate preparations which were made for photographic and spectroscopic observations. The former resulted in a very unprecedented success. One of Dr. Schuster’s photographs of the totality showed not only the expected Corona, but an unexpected comet.

Though on more than one previous occasion in history the darkness which is a special accompaniment of a total eclipse had caused a comet to be seen, yet the 1882 eclipse was the first at which a comet had thrust itself upon the notice of astronomers by means of a photographic plate. It will be remembered that the political circumstances of Egypt in 1882 were of a somewhat strained character and probably this contributed to the development of an unusual amount of astronomical competition in connection with this eclipse. Not only did the Egyptian Government grant special facilities, but strong parties went out representing England, France, and Italy, although not perhaps in set terms at the direct instigation of their respective Governments.

The next eclipse, that of May 6, 1883, had some dramatic features about it. To begin with its duration was unusually long—nearly 5½ minutes, and Mrs. Todd in her genial American style remarks:—“After the frequent manner of its kind, the path lay where it would be least useful—across the wind-swept wastes of the Pacific. But fortunately one of a small group of coral islands lay quite in its line, and, nothing daunted, the brave scientific men set their faces toward this friendly cluster, in cheerful faith that they could locate there. Directed to take up their abode somewhere on a diminutive island about which nothing could be ascertained beforehand, save the bare fact of its existence at a known spot in mid-ocean, the American observers were absent from the United States more than three months, most of which time was spent in travelling, 15,000 miles in all, with ten full weeks at sea. Their tiny foothold in the Pacific was Caroline Island, a coral atoll on the outskirts of the Marquesas group.”

In spite of the unattractive, not to say forbidding, character of the place to which they would have to go, parties of astronomers went out from England, France, Austria, and Italy, and although rain fell on the morning of the day the sky became quite clear by the time of totality and the observations were completely successful. One of the pictures of the Corona obtained by Trouvelot, an observer of French descent, but belonging to the American party, has been often reproduced in books and exhibited the Corona in a striking form. How few were the attractions of Caroline Island as an eclipse station may be judged from the fact that the inhabitants consisted of only four native men, one woman, and two children who lived in three houses and two sheds.

On September 8, 1885, there occurred a total eclipse, which was seen as such in New Zealand, but the observations were few, and with one exception, unimportant and uninteresting. A certain Mr. Graydon, however, made a sketch which showed at one point a complete break in the Corona so that from the very edge of the Moon outwards into space, there was a long and narrow black space showing nothing but a vacuity. If this was really the condition of things, such a break in the Corona is apparently quite unprecedented.

In 1886, on August 29, there occurred a total eclipse, visible in the West Indies, which yielded various important results. It was unfortunate that for the greater part of its length, the zone of totality covered ocean and not land, the only land being the Island of Grenada and some adjacent parts of South America. The resulting restriction as regards choice of observing stations was the more to be regretted because the duration of the totality was so unusually long, and therefore favourable, being more than 6½ minutes in the middle of the Atlantic Ocean. Parties of English, American, and Italian astronomers assembled, however, at Grenada, and though the weather was not the best possible, some interesting photographs were obtained which exhibited an unusual development of hydrogen protuberances. The central line in this eclipse not only stretched right across the Atlantic, but entered Africa on the West Coast where a missionary saw the eclipse as a mere spectator, and afterwards expressed his regret that no astronomers were within reach with instruments to record the remarkable Corona which was displayed to his gaze.

Though the unusual opportunities which, so far as the Sun and the Moon were concerned, were afforded by the eclipse of 1886 were lost, astronomers looked out hopefully for August 19, 1887, when another eclipse was due to happen which, weather permitting, would be observable over a very long stretch of land, from Berlin through Russia and Siberia to Japan. Unusually extensive preparations were made in Russia at one end and in Japan at the other, but clouds prevailed very generally, and the pictures of the Corona which were obtained fell far short in number and quality from what had been hoped for, having regard to the number and importance of the stations chosen, and of the astronomers who made their preparations thereat. An enthusiastic Russian, in the hopes of emancipating himself from the risks of terrestrial weather at the Earth’s surface, went up in a balloon to an elevation of more than two miles. His enthusiasm was so far rewarded that he had a very clear view of a magnificent Corona; but as, owing to some mischance, the balloon rose, conveying only the astronomer and leaving behind his assistant who was to have managed the balloon, all his time was engrossed by the management of the balloon, and he could do very little in the way of purely astronomical work.

The year 1889 afforded two total eclipses of the Sun for which the usual preparations were made. The first occurred on New Year’s Day, and the path of the shadow crossed the North American Continent from California to Manitoba. The weather was nearly everywhere very favourable, and an enormous number of observers and instruments were assembled along the central line. The consequence was that a very large number of photographs were obtained. It may be said generally of this eclipse, that as it coincided with a Sun-spot minimum, it left us in a position to learn very distinctly what are the characteristic features of a solar Corona at a period which is one of rest and repose on the Sun, at least, so far as regards visible Sun-spots.

The second eclipse of 1889 occurred on December 22, and should have been visible off the northern coast of South America and on the West Coast of Africa. Attempts were made to utilise the South American chances by English and American parties, whilst a small expedition comprising astronomers of both nations went to Cape Ledo in West Africa. The African efforts failed entirely owing to clouds, but the South American parties at Cayenne were successful. One very deplorable result, however, arising out of the expedition to Cayenne was the illness and subsequent death of the Rev. S. J. Perry, S.J., who was struck down by malaria and died at sea on the return journey. None who knew Mr. Perry personally could fail to realise what a loss he was both to astronomy generally and to his own circle of friends particularly.

On April 16, 1893, there happened a total eclipse of the Sun, which was successfully watched by a large number of skilled observers throughout its entire length. Indeed it is believed that only one party was unsuccessful. The line of totality started on the coast of Chili, passed over the highlands of that country, across the borders of Argentina and Paraguay, and over the vast plains and forests of Central Brazil, emerging at about noon of local time at a short distance to the N.-W. of Ceara on the North Atlantic seaboard. Crossing the Atlantic nearly at its narrowest part, it struck the coast of Africa N. of the river Gambia, and finally disappeared somewhere in the Sahara. The South American observations were the most extensive and successful, the latter fact being due to the circumstance that the sky at many of the principal stations was pre-eminently favourable, owing to the clearness and dryness of the atmosphere.