936 REPORT—1885. 
on August 19. Unfortunately, bad weather prevented a confirmation, and conse- 
quent announcement of this most important observation. The first published obser- 
vation of the appearance of a bright star in the nebula is that of Dr. Hartwig, at 
Dorpat, on August 31. Estimates of the brightness were found by the writer to 
depend largely upon whether the effect of the nebulosity was eliminated or not. 
Estimates with low powers included some of the nebulosity, and made the star 
appear too bright. The spectrum was observed on various nights, beginning with 
September 1. The spectrum is almost absolutely continuous from end to end, and 
only on the closest scrutiny can the faintest irregularities be even suspected. The 
spectrum extended from W.L, 600™™™ to 456™"™, with a maximum about 544™™™, 
A point less obscure than the rest gave W.L. 482 (not far from F.) On September 3 
Lord Crawford, in company with the author, detected a nebulous nucleus 17/0 
from the bright star. By micrometrical comparison with a neighbouring star, of 
which Lord Rosse gave the relative position in 1851, the author found that this 
nebulous nucleus now visible is really that of the Great Nebula. He then quoted 
from the ‘ Astronomical Register’ of November 1882, as follows: ‘ A small star s.p. 
the nucleus of the great nebula in Andromeda (M. 31) has been suspected of 
variation by the Rev. T. W. Webb. He found the star readily visible on several 
occasions with a 93 inch “ With” speculum, while at other times he found it very 
faint with the same instrument.’ At present there is no star visible, except Dr. 
Hartwig’s, at all corresponding to the one seen by Mr. Webb.! It seemed, there- 
fore, to the author ‘ not unlikely that the true state of affairs is expressed by Lord 
Rosse in a letter dated the 9th inst., viz., “Zt would appear to be the abnormal 
blazing out of a quick, faint, variable star, rather than the appearance of a new star 
which has never been seen before.” ’ The spectroscopic observations are in accord with 
this opinion, for the spectrum is not unlike that of a variable star, while it presents 
no resemblance to that of a genuine blazing star like those of 1866 and 1876. 
4. On Solar Spectroscopy in the Infra Red. By Dr. Dantet Draper. 
In the year 1877 Professor Piazzi Smyth, who had just re-observed in Lisbon 
Brewster's three celebrated lines in the ultra red of the solar spectrum, X, Y, and 
Z, was in correspondence with the late Dr. Henry Draper about them, as being the 
furthest lines visible to the human eye in that direction, and was informed by him 
that his father, Dr. J. W. Draper, claimed these lines, as being the lines he had 
photographed so long before as in 1842, and called a, 8, and y. 
Therefore it became Professor Piazzi Smyth’s rather painful duty to point out 
that that was a mistake ; for the lines a, 8, and y in Dr. Draper's photograph were 
far beyond the possible spectrum places of Brewster's X, Y, and Z. 
But when, in a few years more, Captain Abney by improved photography, and 
then Professor Langley with his admirable bolometer, brought into view whole 
regions of lines beyond and outside Brewster’s furthest X, Professor Piazzi Smyth 
suggested to Dr. Daniel Draper (Dr. Henry Draper having died in the interval), 
that the time had arrived for comparing his father’s primitive photograph of 1842 
with the recent discoveries, and ascertaining whether his lines a, 8, and y cor- 
responded in any way therewith. 
The answer that Dr. Daniel Draper gives, is to the effect that they do cor- 
respond, and in so remarkable a manner as to add great value to photographic 
testimony on a Daguerreotype plate. 
5. The Errors of Seatants as indicated by the Records of the Verification 
Department of the Kew Observatory, Richmond, Surrey. By G. M. 
Wuiprpte, B.Sc., F.R.A.S. 
The author gave the history of the verification of sextants at the Observatory 
from its establishment in 1862, describing the apparatus employed devised by Mr. 
? Unless indeed Lord Rosse’s star is identical with Mr, Webb’s, as was suggested 
by Mr. G. J. Stoney. ote added Nov. 6, 1885. 
