Comet." Mr. Finlay, therein mentioned, was a son of the late Mr. Finlay, Mathematical Master in the Liverpool College, and formerly a member of this Society.

FINLAY'S COMET-DISCOVERY.

By J. B. NEVINS, M.D., M.R.C.S.

THIS brilliant comet was discovered on the 7th September, 1882, by Mr. William Henry Finlay, F.R.A.S., Chief Assistant at the Royal Observatory, Cape Town, a son of the late Mr. William Finlay, who was one of our oldest members, and was so well known in the neighbourhood for his mathematical attainments, and his position as Mathematical Master in the Liverpool College, and tutor to two Senior Wranglers, Mr. Pendlebury and Professor Forsyth, both of whom were Liverpool boys, and received their early training under his instruction.

The following account of the discovery is taken from a lecture delivered before the South African Philosophical Society, by Dr. Gill, the Astronomer Royal at the Cape Town Observatory.

The comet was first discovered on the morning of the 7th September, when it was shining with the brilliancy of a star of the third or fourth magnitude, and showed a not very brilliant tail of about two degrees in length. It was of a very bright white colour. Mr. Finlay had been observing the occultation of a star, and, while returning into the Observatory, his eye was directed to the unusual object, which he recognised to be a comet, and he at once made the necessary observations, which consisted in determining the difference of time in which any small star near the comet passed the lines marked on the telescope, and the time in which the comet passed. They were by these means enabled to identify the star and determine its place, and then to determine the place of the comet. Observations were again

made on the morning of the 8th; and on the morning of the 9th a very rough observation only was possible through the clouds, and then came a series of cloudy days, which rendered it necessary to set about another mode of determining the comet's place. The comet was all the while increasing in brilliancy, until, on the Sunday morning, Mr. Finlay and Dr. Elkin observed it quite plainly by daylight. Towards the afternoon they found it approaching the sun with enormous rapidity, until it was evident that it would actually pass either behind or in front of it. At that time it was impossible to say whether the comet was behind or in front of the sun. They watched it until it approached nearer the sun, and its tail vanished, and there only remained a small round disk, which did not appear to diminish as it approached the sun, but rather to get brighter, and was distinctly visible through the dark glass necessary to use in observations of the sun. The comet came close up to the sun, and Dr. Elkin and Mr. Finlay watched it until it was lost in the wavy outline in passing by the edge of the sun. They continued to watch it until they lost all trace of it, and there were only five seconds difference in time in the observations of the two observers, showing that both must have seen it very nearly, if not quite, to the edge of the sun. The next question was whether it had passed behind or in front of the sun. They therefore made an examination of the neighbourhood of the sun where the comet had disappeared, but nothing was to be seen, so they thought it was possible that it had gone beyond the sun.

APPEARANCE OF THE COMET.

When the comet was first seen it had very much the appearance which many of the comets possessed-a sharp nucleus, and a long retreating tail like a parabolic cylinder; but about the 22nd or 23rd September the comet's head

began to do a most singular thing. Its nucleus, instead of remaining single, began to get longer, and then elongated still more, until there were two little nuclei connected by a strong-looking thread between them. Then they elongated still more, until on one morning Mr. Finlay counted no fewer than five of these nuclei extending to the length of a minute of arc, the original nucleus remaining the largest and most brilliant.

In the photograph which was taken by Mr. Ellis, of Rosebank, on the 20th of October, these nuclei are not distinguishable separately from the original large, brilliant nucleus, and the tail is partially divided near its end into two diverging portions, resembling the division of a fish's tail. Four stars of considerable brilliance are distinctly seen through the tail.

DATE OF ANNOUNCEMENT.

The comet was first observed on the morning of the 7th September, and on the 9th September Dr. Gill telegraphed to the Astronomer Royal in England that this comet had been discovered by Mr. Finlay, and giving its position. There were telegrams from Paris and Vienna on the 27th September, stating that a brilliant comet had been seen in a position which corresponded with the place of this particular comet, but this discovery of theirs was nineteen days after it was seen by Mr. Finlay, and seventeen days after the telegram had been despatched by him to England. Through some mischance, however, the telegram was mislaid-and he might say that this was the first telegram of his that had not at once reached its destination-and the first telegrams that reached England on the subject were from Rio de Janeiro, and from the Observatory of the Sultan of Zanzibar. But owing to bad weather in England, the comet was there lost sight of for some time. He had dwelt upon

the discovery of the comet on account of his friend Mr. Finlay's connection with it.

IS THIS A NEW COMET OR AN OLD ONE RETURNING?

At the conclusion of Dr. Gill's lecture Mr. Finlay gave some account of the elements of the orbit of the comet, and the rapidity with which it passed its perihelion. The elements of the comets of 1843, 1880, and the present one, were very much like each other, but there were some slight changes, and the intervals were so unequal that he was decidedly of opinion that this was not the return of a comet. In reply to a question by the Chief Justice (Sir J. H. de Villiers), Mr. Finlay said the comet had actually passed through the corona of the sun.

Dr. WHITTLE then read a paper on "The Census of 1881."*

FIFTH ORDINARY MEETING.

ROYAL INSTITUTION, 11th December, 1882.

EDWARD DAVIES, F.C.S., F.I.C., PRESIDENT, in the Chair.

Mr. George Alexander Mather was duly elected an Ordinary Member.

Dr. SHEARER exhibited the crude materials from which the Superphosphates of Commerce are obtained. These were of two kinds :-1. A Canadian phosphatic rock, known as Apatite, in fine, massive hexahedra of an opalescent green colour, and the same intermixed with mica. 2. A Marl

* See page 99.

from Carolina, abounding in organic remains, sharks' teeth, whales' vertebra, coprolites, and conchiferous bivalves.

Mr. JOHN LINTON PALMER, F.S.A., F.R.G.S., Fleet Surgeon R.N., read a paper on "Runes." *

SIXTH ORDINARY MEETING.

ROYAL INSTITUTION, 8th January, 1883.

EDWARD DAVIES, F.C.S., F.I.C., PRESIDENT, in the Chair.

The Rev. HENRY H. HIGGINS, M.A., made a communication on "Peripatus Capensis," discovered by Professor Moseley at the Cape of Good Hope, who had recently presented a specimen to the Free Public Museum.

NOTE ON A VAST SEA OF PYROSOMA OR SALPE OFF THE ISLAND OF SOCOTRA.

Mr. JOHN LINTON PALMER, F.S.A., F.R.G.S., read a short extract from a letter from Captain F. P. Doughty, H.M.S. "Constance," descriptive of a vast sea of "Pyrosoma," as seen off the island of Socotra, 20th Sept., 1879.

"This evening H.M.S. "Crocodile" had to stop steaming. Huge banks of Salpæ had risen at nightfall to the surface, choking the condensers, &c., by preventing the water coming through the strainers, so no vacuum would be produced. Afterwards the condensers became heated-the strainers were taken off and cleaned three times, but all attempts to proceed failed. At daybreak the Salpæ sank, the ship was

*See page 143.