SCIENCE-ADVERTISEMENTS 



The University of California Press 



Berkeley, CaUfornls 280 Madison Arenne, New Tork 



10 



The Effect of Certain Aluminam Com- 

 pounds on the Metabolism of Man 



By C. L. A. Schmidt and D. R. Hoaqland $ .35 



The Action of Ultraviolet Light on Certain Bac- 

 teria in Relation to Specific Absorption by 

 Amino Acids. By Feanklin I. BLabris and 

 Hubbard 



Further Studies on the Distribution and Activ- 

 ities of Certain Groups of Bacteria in Cali- 

 fornia Soil Columns. By Charles B. 

 LiPMAN 10 



The Wintun Hesi Ceremony. By S. A. Barrett .60 



Table of PH, H-|- and OH- Values Correspond- 

 ing to Electromotive Forces Determined in 

 Hydrogen Electrode Measurements, with a 

 Bibliography. By Carl L. A. Schmidt 

 and D. R.Hoagland 



Reactions of Various Plankton Animals with 

 Reference to their Diurnal Migrations. By 

 C. O. ESTEBLT • • • 85 



The above titles represent University of California 

 Publications m Agricultural Sciences, Botany, American 

 Archaeology and Ethnology, Pathology, and Zoology. 

 Other series published by the University of California 

 include: Entomology, Geography, Geology, Physiology, 

 and Psychology. 



Complete Lists of Titles and Prices will be sent 

 on Request 



50 



for the Inference Library 



Wiley's 



Beverages and 



their Adulterations 



42 Illustrations. 8vo, xv-f421 Pages. Cloth, S3.50 

 Postpaid. The Origin, Composition, Manufacture, 

 Natural, Artificial, Fermented, Distilled, Alkaloidal and 

 Fruit Juices. By HARVEY W. WILEY, M.D., form- 

 erly Chief of Department of Chemistry, U. S. Bureau 

 of Agriculture ; Author of " Foods and Their Adultera- 

 tion." 



From the Preface: The rapidly increasing use of 

 fruit juices demands a prominent place in this volume, 

 for their description and composition. The many so- 

 called soft drinks which will undoubtedly have a greater 

 vogue as the area in which alcoholic beverages are 

 manufactured and sold decreases; warrant a rather full 

 description of them here. The so-called medicines 

 which consist chiefly of alcohol, and which are held by 

 the Bureau of Internal Revenue as non-medicinal, but 

 alcoholic, are fully described. 



Proper space is given to a discussion of coffee, and re- 

 lated products^ tea, cocoa, chocolate. Water with pot- 

 able waters, mineral waters, artificial and natural, are 

 included. With each subject treated are described the 

 common adulterations and misbrandings which may be 

 practiced therewith. 



P. Blakiston's Son & Co., Philadelphia 



Cooking Class at tKe 

 Sotttli Dakota State College 



are using GAS made by 



The "Detroit" 

 Combination Gas Machine 



for supplying gas in Departments of 



Domestic Science 

 Chemistry and Physics 



(Otter 30,000 in duly ose) 

 Laboratory work can be done better, 

 quicker and cheaper by using this gas. 

 Ask for descriptive catalog and names 

 of users in your vicinity. 



Detroit Heating & Lighting Co. 



612 Wight St. Detroit, Midi. 



E>t. 1868 



Northnip Millivolter 



Slade under tlie Pyrovolter Patents 

 of November 6, 19X7 



The new NORTHRUP MILLIVOLTER is a 



standardized portable deflection potentiometer, 

 working on tiie Pyrovolter Principle. 



This instrument oiTers a convenient means 

 for the accurate measurement of e.m.f.s. up to 

 one volt, without the abstraction of any current 

 from the source of the e.m.f . being measured. 



The MILLIVOLTER should generally be 

 used in place of a millivoltmeter. where accuracy 

 is of importance. It is valuable for taking the 

 voltage drop in motors, for the measurement of 

 low voltages over electrolytic baths where a 

 carefully measured current is flowing, for use in 

 thermocouple pyrometry, for measuring the in- 

 ternal resistance of dry cells, and for accurate 

 measurement of large currents by reading the 

 voltage drop over a low known resistance. 



The MILLIVOLTER has one hand-drawn 

 scale and three ranges : o-io mv., o-ioo mv., 

 and o-iooo mv. It is described in Circular No. 

 9, which awaits your request. 



PYROLECTRIC rNSTRUMENT CO. 



Pyrometric and Electiical Prediion iutrumtnU 



636 EAST STATE STREET TRENTON, N. J. 



E. F. Northnip, Pruident and Technical AdriKr 



