ra SCIENCE.—ADVERTISEMENTS. 
NEW SCIENTIFIC BOOKS—Just Ready or in Press 
The Liquefaction of Gases 
Just Ready. Irs RIsE AND DEVELOPMENT. Cloth, 12mo, $1.50. 
By WiLutert LerLey Harbin, Harrison Senior Fellow in Chemistry in the University of Penn- 
sylvania. 
A complete history of the development of the methods employed in the liquefac- 
tion of gases, as the following clipping from the preface will show : 
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the Book of the methods employed in the liquefaction of gases. Sufficient theory has been given to 
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Industrial The various forms of apparatus are shown in illustrations. In addition to the history 
Application of the development of the methods, the condition of matter at the critical point, the theory 
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at low temperatures and of the industrial application of liquefied gases. 
THOMPSON—Light Visible and Invisible. | SUTER—-Handbook of Optics. For Srv- 
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wus P. THompson, D.Sc., M.R.I., F.R.S., author WOOD SuTER, M.D., Professor of Ophthalmology, 
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BURBURY—A Treatise on the Kinetic 
Theory of Gases. By S. H. BurBury, M.A., 
F.R.S., late Fellow of St. Johns, Cambridge. 
8vo, Cloth. Price, $2.00 net. 
Cambridge University Press. 
LANGE—Our Native Birds. How To Pro- 
TECT HEM AND ATTRACT THEM TO OUR HomMEs. 
By D. LANGE, Instructor in Nature Study in the 
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MACBRIDE—The Slime Moulds. A HAND LENGFELD—Inorganic Chemical Prepa= 
BOOK OF NORTH AMERICAN MYXOMYCETES. By rations. By FELIx LENGFELD, Assistant Pro- 
THomaAS H. MACBRIDE, Professor of Botany, Uni-_ 
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A list of all species described in North America 
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fessor of Inorganic Chemistry in the University of 
Chicago. Cloth, 16mo, 60 cents nef. 
This book gives directions for making about fifty 
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some knowledge of analytical chemistry. 
Blowpipe Analysis 
By FREDERICK Hurron GETMAN, Instructor in Chemistry in Stamford High School. Cloth, 
16mo. Just Ready. 60 cents net. 
This little book is designed for use in high schools, and also to serve as an aid to college students in 
the study of qualitative analysis. 
THE MACMILLAN COMPANY, Publishers, New York. 
