D. VAN NOSTRAND. 19 
Nugent on Optics. 
12mo. Cloth. $2.00 
TREATISE ON OPTICS ; or, Light and Sight, theoretically and 
practically treatad ; with the application to Fine Art and Indus 
trial Pursuits. By E. Nugent. With one hundred and three 
illustrations. 
« XMs book is of a practical rather than a theoretical kind, and is de- 
signed to afford accurate and complete Information to all interested in appli- 
cations of the Science.”—Rottn-d Takle. 
Barnard’s Metrie System. 
8vo. Brown cloth. $3.00. 
THE METRIC SYSTEM OF WEIGHTS AND MEASURES. 
An Address delivered before the Convocation of the University of 
the State of New York, at Albany, August, 1871. By Frebeeick 
A. P. Baknakd, President of Columbia College, New York City. 
. Second edition front the Revised edition printed for the Trustees 
of Columbia College. Tinted paper. 
«It is the best summary of the argumenta in favor of the metric weights 
and measures with which we are acquainted, not only because it contains in 
small space the leading facta of the caae, but because it puts the advocaoy of 
that System on the only tenable grounds, namely, the great conven.ence of a 
decimal notati'on of weight and meanure aa wellas money, the value of inter 
national nniformity in the matter, and the fact that this metric System is 
adopted and in general use by the majority of civilized nations.”- TU Natwn. 
The Yonng Meohanio. 
lllustrated. 12mo. Cloth. $1.(5. 
THE YOTTNG MECHANIC. Containing directions for the use 
of all kinds of tools, and for the construction of steam engines 
and mechanieal models, including the Art of Turning in Wood 
and Metal. By the author of “The Lathe and its Uses,” etc 
From the English edition, with corrections.