416 Astronomy. 
application of this method to the motion of the moon constitutes 
the Sonera or Bay technical part of the work; while the 
history of the problem the comparison of the results obtained, 
with the sorreaponditie’ results of _ calculators, is given in 
considerable detail in the introducti 
The author believes that he bas yp Re ‘wo equations of 
the third order of magnitude having a short period, besides other 
terms of Ion riod depending on the sun’s action and on the 
oblateness of the earth, which have not been before correctly 
computed, and which are of very pores epee in the 
lunar theory. Should these results be confirmed by other ea 
tors, the remark of the late Astronomer aval Sir &,.B. 
made some eight years ago, namely: “that there is some tau 
defect in the lunar theory,” will be fally justified. 
This is the first book published in this country, which is wholly 
devoted to the mathematical development of the general theory 
of the moon’s motion, as affecte the sun’s attraction ; 
impor rtant papers have been published at different times in the 
various scientific journals of the country, upon some Lada sy 
cases of lunar perturbation due to the sun’s action. roblem, 
though old, is sau one of the most interesting and in spartan in 
celestial mechani s; and it is to be hoped that a American 
mathematicians will interest themselves in its soluti 
The book contains about four. hundred pages, oe in this 
respect contrasts happily with the great works of Plana and 
Delaunay, which, sega Ee aaher cove’ considerably more than 
ai thousand pa 
is printed in Fandeonie style, on excellent paper. Aside from 
ani ae cpr of the subject of which it treats, it 
e of beautiful solutions of problems which are 
ivive of ie to pg! student of the pure mathematics; and 
we cordially commend it as worthy of a pee} in all the scientific 
libraries of the country, wholes public or private. 
stronomical and oe ee uations made during 
the. Lie! 1876 at the U.S. N. Observatory. Rea ees 
s, Superintendent. Government ‘Printing Office, 18 80. —This 
opr baton of the Naval Observatory to science fills two thick 
quarto volumes, one containing the regular observations and the 
other made up of three i impor tant appendices. The first appendix 
is a subject index (of 74 pages) tempered by Prof. Holden, to all 
the publications of the U.S. N. Observatory. It makes the valu- 
able material that is scattered “ae h these volumes far more 
easily accessible than heretofore to astronomers. The second 
appendix (of 126 press contain the several reports on the transit 
of Mereury, in May, 1 The third appendix, on the solar 
eclipse of July, 1878, ae pear already noticed (this pice ate 
vol. xxi, p. 334). 
OBITUARY. 
Dr. G. Liynarsson, paleontologist of the Geological Survey 
of Sweden, died recently at the age of forty years. 
