Opinions of the Press on the “ International Scientific Series.” 
XVIL 
Money and the Mechanism of Ex- 
change. 
By W. STANLEY FEVONS, M.A., F.R.S., 
Professor of Logic and Political Economy in the Owens College, Manchester. 
tvol., 12mo. Cloth. Price, $1.75. 
, He offers us what a clear-sighted, cool-headed, scientific student has to say on the 
nature, properties, and natural laws of money, without regard to local interests or na- 
tional bias, His work is ‘popularly written, amd every page is replete with solid instruc- 
tion of a kind that-is just now | bly ded by multitudes of our-people who are 
victimized by the grossest fallacies.” —Popular Sceence Monthly. : 
“If Professor Jevons’s book is read as extensively-as it deserves to be, we shall 
have sounder views on the use and abuse of money, and more correct ideas on what a 
circulating medium really means.”—Boston Saturday Evening Gazette, 
“« Professor Jevons writes in a sprightly but colorless style, without trace of either 
prejudice or mannerism, and shows no commitment to any theory. The time is not 
very far distant, we hops, when legislators will cease attempting to legislate upon 
money before they know what money is, and, as a possible hel, d such a change, 
Professor Jevons deserves the credit of having made a useful contribution to a depart- 
ment of study long too much neglected, but of late years, we are gratified to say, be- 
coming less so."—The Financier, New York, 
XVIII. 
The Nature of Light, 
WITH A GENERAL ACCOUNT OF PHYSICAL OPTICS. 
By Dr. EUGENE LOMMEL 
Baste {University of Erlangen). ~ : 
I vol., 1z2mo. Cloth. " a % Price, $2.00. 
“In the present treatise, Professor Lommel has given an admirable outline of the 
nature of light and the laws of optics. 
‘Unlike most other writers on this subject, the author has, we think, wisely post- 
poned all reference to theories of the nature of light, until the laws of reflection, re- 
fraction, and absorption, have been clearly set before the reader. Then, in the fifteenth 
chapter, Professor L 1 di Fresnel’s fa interfe peri _and 
leads the reader to see that the undulatory theory is the only conclusion -that can be 
satisfactorily arrived at. -A clear exposition is now given of Huyghen’s theory, after 
which follow several chapters on the diffraction and polarization of light-bearing waves. 
ta, “ The reader is thus led onward ‘much in the same way-as the science itself has un- 
folded, and this, we think, is the surest and best way of teaching natural knowledge. - 
»’ “ Wehave said enough to show that Professor Lommel’s treatise is a useful contii- 
bution to the ‘ International Series’—a book that can thoroughly be understood and 
enjoyed by any intelligent reader who may not have had any special scientific ‘train- 
ing.” —Nature.. > oo ~ Bete «lim 2 
“Tia style singularly lucid, idering the at nature of: the subject treated, 
Dr. Lommel unfolds the learning of the scientists on the nature and. phenomena of 
light."—Puuladelphia Inquirer. 4 
As a‘popular introduction to physical optics, it would be difficult to find-a more 
satisfactory work than:the one by Dr. Lommel, which has just appeared in the excel- 
lent ‘ International Scientific Series.’ "—T7he English Mechanic. : 
D. APPLETON & CO., PUBLISHERS, .549 & 551 Broadway, N. Y. 
