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known to "be quite imperfect. At the June meeting of the Royal Astronomical 
Society, Prof. Adams communicated a further paper containing a proof in 
an elementary form of the accuracy of his own value, impugned as incorrect 
by Sir George Airy. This paper was published in the middle of August. 
Although some rejoinder may be looked for from Sir George Airy, there can 
be no doubt, after Prof. Adams’ conclusive reply, that the Astronomer 
Royal has been led into error by the form he has given to his in- 
vestigations. 
A singular point in this controversy may be mentioned. There has 
always been a desire to reconcile the observed value of the acceleration in 
the motion of the Moon with that arising from the diminution in the 
eccentricity of the Earth ; but whereas the former seemed to amount to 
over 12"*2, the latter was only 6" # 2. It was this discrepancy which probably 
led Sir George Airy to take up the subject. But quite lately the researches 
of Prof. Newcomb have clearly shown that this value of 12"*2 is a great 
deal too large, and arises from an error in Hansen’s Tables of the motion of 
the Moon. Correcting this error, Prof. Newcomb is able to show that the 
secular acceleration is probably less than 8"*3. It has been shown, subse- 
quently, by Mr. Neison, that if one of the most discordant of the ancient 
eclipses be omitted, all the rest are in harmony with the value of the secular 
acceleration of 7"'2, and are more in harmony with the value 6"*2 than with 
any value greater than 8"*0. It is not at all improbable, therefore, that 
before long further improvements in the lunar theory wall reconcile the 
observations with Prof. Adams value of the secular acceleration, and that 
Sir George Airy’s value, instead of reconciling theory and observation, as he 
supposed, would have thrown them into intolerable discord. 
Record of the Progress of Astronomy during the year 1879. — Under this 
title there has been compiled by Mr. J. L. E. Dreyer, M.A., of the Observa- 
tory of Trinity College, Dublin, a very useful account of the principal 
astronomical events of the past year, and it has been published as a memoir 
by the Royal Dublin Society in their Scientific Proceedings , and reprinted 
therefrom in an octavo pamphlet of some fifty pages. Mr. Dreyer prefaces 
his summary as follows : — 1 In the following pages I shall endeavour to 
sketch the principal astronomical events of the past year, giving short 
accounts of the more important or interesting investigations which have 
been published during this period. For the year 1878, such an account was 
written by Prof. E. S. Holden, of the United States Naval Observatory, 
for the Annual Record of Science and Industry ; and as I have learned from 
him that this publication has been discontinued, I have thought it might be 
of some use, both to professional astronomers and to amateurs, if a con- 
tinuation of his record was kept up, giving summaries of the work done in 
the various branches of Astronomy, merely intended to draw attention to 
w r hat has been done in them. It had at first been my intention to add to 
this review a bibliographical list of books and memoirs in Astronomy pub- 
lished during 1879, but for various reasons I have left it out. It might be 
better to let such a list embrace a longer lapse of time than one year ; and, 
besides, the Bibliographie Generate, the publication of which has recently 
been announced from the Brussels Observatory, is to include the year 1880. 
The present record does not aim, therefore, at any completeness, but only at 
