506 
REVIEWS. 
The Student's Manual of Geolooy. By Professor J. B. Jukes, M.A., 
F.R.S. Black. 
W HEN one remembers that in a subject so well understood as arith- 
metic, it is only within the last few years that a good student’s 
text-book has been written, it is perhaps too much to expect perfection in 
any manual of geology. Nor is it to be found in this one, which is some- 
times dwarfed in plan, and occasionally erroneous in theory and fact. It 
is, however, by far the best book in our language for the real student : 
philosophically conceived, it treats in dependent succession, and at length 
somewhat commensurate with their relative importance, of all the subor- 
dinate parts of geology. It has been too much the custom to give in 
manuals only some of the last results of science in the history of the 
earth’s crust ; here, however, the student is introduced to the machinery 
by which these conclusions are won, and by mastering which he may 
work out more. The first part, admirably treated, and forming half the 
book, deals with rocks from a physical point of view ; the second part 
is palaeontology and limited to fifty pages ; so that the third part, which 
is the history of stratified rocks, worked out by means of geognosy and 
palaeontology, does not follow naturally. This subject of old life might 
have been treated typically, without trespassing on Owen’s “ Palaeonto- 
logy,” so as to give the student better help than the chapters on laws 
of life, which are in many cases only guesses never yet challenged ; the 
third part is excellently illustratecUwith figures of 320 of the more cha- 
racteristic fossil species, and numerous sections and diagrams, of which the 
book contains 125. In this portion the author’s careless treatment of the 
biological part is occasionally evident in the way in which genera still 
living are marked as extinct. These, however, are slight defects, and of no 
moment for the student, who will treasure the book, and find himself 
enticed onwards by the luminous writing. 
RECENT WORKS ON ASTRONOMY. 
The Orbs of Heaven. New Edition. Popular Astronomy. New Edition. 
By 0. M. Mitchell, LL.D. Routledge. 
P ERHAPS, as Professor Mitchell is an American, and as his 
country has of late been associated in our minds chiefly with strife 
and bloodshed, there may be many amongst our readers who have neither 
heard of him, nor yet had the privilege of reading his works. 
