30 SCIENTIFIC BOOKS PUBLISIIED BY 
Ward’s Steam for the Million. 
New and Revised Edition. 
8vo. Cloth. $1.00. 
STEAM FOR THE MILLION. A Populär Treatise on Steam 
and its Application to the Useful Arts, especially to Naviga 
tion. By J. H. Ward, Commander IT. S. Navy. New and re- 
vised edition. 
A most excellent work for the young engineer and general reader. Many 
facta relating to the management of the boiler and engine are set forth with a 
simplicity of language and perfection of detail that bring the subject hörne 
to the reader.—American, Engineer. 
Walker’s Screw Propulsion. 
8vo. Cloth. 75 cents. 
NOTES ON SCREW PROPULSION, its Rise and History. By 
Capt. W. H. Walker, U. S. Navy. 
Commander Walker’s book contains an immense amount of concise practi- 
cal data, and every item of information recorded fully proves that the various 
point3 bearing upon it have been well considered previously to expreesing an 
opinion.—London Mining Journal. 
Page’s Earth’s Crnst. 
18mo. Cloth. 75 cents. 
THE EARTH’S CRUST: a Handy Outline of Geology. By 
David Page. 
“ Such a work as this was much wanted—a work giving in clear and intel- 
ligible outline the leading facts of the Science, without amplification or irk- 
some details. It is admirable in arrangement, and clear and easy, and, at the 
Barne time, forcible in style. It will lead, we hope, to tho introduction of 
Geology into many schools that have neither time nor room for the study of 
large treatises.”—The A.useum.