EEYIEWS. 
293 
differs from that practised by any other North American tribe ; further, 
they were idolaters, and the physiognomy of many of their idols more or 
less resembles that of some of the Toltec idols. Both the headdresses and 
physiognomy of some of the idols are suggestive of an Eastern or Chinese 
origin. Their connection with Central America and the Gulf of Mexico is 
indicated by the presence of numerous large sea-shells in the mounds, by 
the representation of Central American birds and animals on their pipes and 
culinary vessels, and by their making use of obsidian, fluor-spar, and ser- 
pentine for constructive purposes. 
The description of the “ Archaeological Collection of the United States 
National Museum,” by Mr. Charles Rau, which forms the second part of 
the Smithsonian Contributions for 1876, is a most important contribution to 
the knowledge of American archseologv. Implements, weapons, and orna- 
ments, articles of stone, clay, metal, wood, shell, bone, and horn, are most 
carefully described and profusely illustrated, so that the book will form an 
excellent treatise of reference for all future students. 
ELEMENTARY PHYSICS.* 
"lyrO branch of science is more popular than that which we used to call 
-i- ' Natural Philosophy, and which most people now-a-days call Physics. 
Nor is this to be wondered at. Eor the forces of nature, though unseen 
themselves, are constantly manifest in their effects upon the world of matter 
around us ; and a person endowed with ordinary curiosity must needs be 
anxious to learn something about such phenomena as those of gravitation, 
heat, light, and electricity. For imparting a sound knowledge of physics, 
we can hardly point to any better elementary work than the well-known 
Treatise of Deschanel, which has been much improved by Professor Everett 
in the English translation. But this beautifully-illustrated work is perhaps 
a little too elaborate for the beginner, and hence the translator and publisher 
have thought fit to bring out an introductory text-book, dealing with similar 
subjects. The result is the excellent little work now in our hands. What 
should, and what should not, be introduced into such a work is, of course, 
in large measure a matter of individual opinion ; but Professor Everett, as a 
teacher of long experience, has in most cases exercised great judgment in the 
selection of his materials. The wisdom of his discretion is seen in the way 
in which he avoids details, whilst dwelling on general principles ; not cram- 
ming the beginner with a multitude of facts, but rather teaching him to con- 
nect a few great facts together. It need hardly be said that the most modern 
views are everywhere introduced, and that Professor Everett has taken an 
early opportunity of employing the modern C. G. S. system of units ; that is 
to say, the Centimetre, the Gramme, and the Second are taken as the 
units respectively of length, mass, and time. A Dyne is the new name for 
the unit of force ; a dyne is therefore that force which, acting upon a mass 

* “ Elementary Text-book of Physics.” By J. D. Everett, M.A., D.O.L 
F.R.S.E., &c. Sm. 8vo. London : Blackie & Son. 1877. 
