Page:Transactions NZ Institute Volume 9 Supplement.djvu/32

640 'Proceedings of the New Zealand Institute.' Accidentally, I, the other day, found Dr. Gray's letter, and now send you the extract from it which relates to the rat-skin which I sent to him:—

2. "Description of a new Species of the Genus Cicindela," by Captain T. Broun. (Transactions, p. 374.)

3. "Description of some new Species of Coleoptera," by Capt. T. Broun. (Transactions, p. 371.)

New Members.—F. G. Ewington, D. Fallon, A. Rubery.

1. "Notes on the approaching Eclipse, to take place on 18th September, 1876," by T. Heale.

From the time of the publication of Mr. Bailly's paper, in 1836, on the luminous prominences seen round the limb of the moon during a total eclipse—and which were thence named "Bailly's beads"—down to the eclipse of 1870, total eclipses of the sun were looked to by astronomers and physicists with the greatest anxiety; and expeditions were fitted out to the most distant places to observe the phenomena of the corona with the best procurable instruments. The suggestion made by Mr. Norman Lockyer, in 1866, and afterwards independently by M. Janssen, while observing the eclipse of August, 1868—that the prominence lines in the corona, which until then had only been seen in eclipses, might be rendered visible during sunlight by the use of spectroscopes with sufficient dispersive power—has taken away almost all the interest from the phenomenon, and we hear no longer of expeditions for its observation; but, still, we ought not to pass over the occurrence of an eclipse which will be total very near to us, and which will be large here, without some notice.

The eclipse of the 18th of this month will be total over a long oblique line, from about lat. 58° S. to near the equator; and from long. 85° W. to 145° E. The line of totality will, however, be very narrow along the whole of that long line: it will vary from about 15 miles where the moon is near the horizon, to about 55 miles in width where the moon is vertical, and her shadow is consequently widest. The times, therefore, during which the total phase of the eclipse will last will vary from 29sec. to 1min. and 48sec.

Here, about one-half the sun's disc will be covered: the first contact will be a few seconds after eight in the morning (Telegraph time), the greatest phase will be reached at nearly nine minutes past nine, and the last contact will be at 10hr. 17min. 24sec.

At the East Cape the eclipse will be considerably larger, nearly two-thirds of the sun's diameter being covered. At Wellington, the times of first and last contact will be slightly different, and ·48 of the sun's disc obscured.

The accurate computation for any particular place of the circumstances of a solar eclipse from the elements given in the Nautical Almanac is a very simple and easily