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POPULAR SCIENCE REVIEW. 
laws regulating tlie constitution of bodies are concisely stated ; their history 
and progressive development being described at some length, the writer 
beginning with the discoveries of Clarke and Griffin, and terminating with 
those of Gerhardt, Laurent, Williamson, Frankland, Kolbe, and others. 
Exercises to be worked out by the reader are scattered through the text, 
and the appendix contains a useful list of questions given by various 
examining boards. We trust Mr. Galloway’s handbook may meet with 
the encouragement it deserves; it commends itself to every serious 
student of chemistry. 
F the three volumes which we are about to notice, the first is 
unquestionably the most important. It treats of mechanics, hydro- 
statics, pneumatics, hydraulics, acoustics, and animal mechanics. The style 
is vigorous and clear, and the language is so characterized by an absence 
of technicality, that the book may be read with as much advantage by an 
ordinary reader as by a student. The author does not confine himself to 
mere descriptions of machinery and explanations of their mode of action, 
but allows a wholesome and philosophic tone to pervade his remarks, by 
which the reader’s mind cannot fail to be improved. That stumbling-block 
of amateur mechanics, the centre of gravity, is explained in the simplest 
manner; and the chapter on the science of music furnishes more details 
than are usually to be found in works like the present one. The different 
laws of natural philosophy are tersely and popularly expressed, and the 
diagrams, which are numerous, are simple and explicit. The least accurate 
portion of Dr. Arnott’s production is that which relates to pure physiology. 
The statement that, till two hundred and fifty years ago, man was “ igno- 
rant of the fact that the blood in his own body is constantly travelling from 
the heart to all other parts and back again,” is not exactly correct. On 
consulting M. Flouren’s essay, “ Histoire de la Decouverte de la Circula- 
tion du Sang,” Dr. Arnott will perceive that even in the time of Csesalpinus, 
the expression “ circulation of the blood ” had been employed. 
Mr. Lynn’s little volume, though of modest size, is very well executed, 
and as a student’s manual takes a higher rank than the work just noticed. 
Its object is to supply in a small compass an account of the fundamental 
principles of the sciences of mechanics, hydrostatics, hydraulics, pneu- 
matics, and optics. It is clearly written, and, without pretending to be a 
popular treatise, may be read by those familiar with the early books of 
* “ Elements of Physics, or Natural Philosophy.” By Neil Arnott, 
M.D., F.R.S. London : Longman & Co. Sixth edition. Part I. 
1864. 
“ First Principles of Natural Philosophy.” By W. T. Lynn, B.A., &c. 
London : Van Voorst. 1863. 
“The Ghost as produced in the Spectre Drama,” &c. By Henry 
Dircks, C.E. London : E. & F. Spon. 1863. 
NATURAL PHILOSOPHY.* 
