404 
Analyses of Books. 
TJune, 
The following remark on the pra&ical value of Palaeontology 
is worth recording “ The sums which have been expended by 
private enterprise in the search for coal in the different States ol 
the Union, in places where anyone possessing the merest rudi- 
ments of palaeontological knowledge would have known better, 
is enormous, and this waste of labour and capital can be stopped 
only by a proper diffusion of the knowledge referred to. 
We find an account of the so-called “ spring’’ of the rattle- 
snake, which has been much exaggerated “ The head, neck, 
and upper portion of the body, which may be raised to the height 
of more than a foot from the ground, are curved slightly back- 
ward, and then thrown forward with great violence. So tar as 
we observed, the distance of the spring may amount to about 
two thirds the length of the snake. 
A valuable feature of the volume is the Report on the Lre- 
taceous Fossils of the Western States and Territories, by Dr. 
C. A, White. 
A Treatise on Statics t containing the Fundamental Principles of 
Electrostatics and Elasticity. By G. M. Minchin, M.A. 
Second Edition. (Clarendon Press Series.) London and 
Oxford : Macmillan. 
The work before us, as compared with the former edition con- 
tains several important improvements. Not only has it been 
largely, if not entirely, freed from those misprints and clerical 
errors which in a mathematical book are at once so serious an 
so difficult to avoid, but the examples have been re-arrange in 
the order of their respective difficulty. Further, the demon- 
stration of the parallelogram of forces has been based entirely 
on Newton’s definition of force. The work is further ennche 
with the principal propositions of graphic statics. 
The seCtion dealing with electrostatics has been enlarged, and 
a chapter on Strains and Stresses has been introduced. On this 
subieCt the author remarks : — “ In view of the enormous deve- 
lopment of mathematical physics, and the wonderful inventions 
depending on the small strains and vibrations of natural solids 
which have been made within the last few years, the study ot 
the equilibrium and motion of bodies as they are, and not as 
they appear in abstraction, is surely a subjeCt of which it is 
impossible to exaggerate the importance. We may well ask 
whether, in this country, too much time is not spent in the dis- 
cussion of neat mathematical unrealities— in the calculation ol 
the behaviour of impossible bodies under impossible circum- 
stances.” 
