908 



SCIENCE. 



[N. S. Vol. XI. No. 284. 



a Viscous Liquid when Referred to Cylindrical 

 and Polar Co-ordinates,' by Professor P. E. 

 Doudna, ' The Capricorns, Mammals of an 

 Asiatic Type, Former Inhabitants of the Pike's 

 Peak Region,' by Dr. F. W. Cragin ; ' Buchi- 

 ceras (Sphenodiscus) Belviderensis and its Vari- 

 eties,' by Dr. F. W. Cragin; 'The Number 

 Concept,' by Dr. F. Cajori. 



BOOKS EECEIVED. 



Das Tierreich, 9 Lieferung, Aves-Trochilidae. Ernst 



Haktebt. Berlin, R. Friedliinder und Sohn. 



1900. Pp. ix + 254. Subscription price, 12 mark. 

 Bird Shidies n'iih Camera. Frank M. Chapman. 



New York, D. Appleton & Co. 1900. Pp. xiv 



+ 214. 

 La speleologie ou science des caoernes. E. A. Mae- 



TEL. Paris, Georges Carr6 & C. Naud. 1900. Pp. 



126. 

 JEther and flatter. Joseph Larmor. Cambridge, 



The University Press. New York, The Macmillan 



Company. 1900. Pp. xxviii + 365. 10s. 



SCIENTIFIC JOURNALS AND ARTICLES. 



The American Journal of Science for June 

 contains the following articles : 



Method of Studying the Diffusion (Transpiration) 

 of Air through Water, and on a Method o£ Barom- 

 etry. C. Bakus. 



Separation and Determination of Mercury as 

 Mercuroua Oxalate. C. A. Peters. 



Electrical Resistance of Thin Films Deposited by 

 Cathode Discharge. A. C. Longden. 



New Meteorite from Oakley, Logan County, Kan- 

 sas. H. L. Preston. 



Observations ou Certain Well-Marked Stages in 

 the Evolution of the Testudinate Humerus. G. R. 



WlKLAND. 



Chemical Composition of Sulphohalite. S. L. 

 Penfibld. 



Phases of the Dakota Cretaceous in Nebraska. 

 C. N. Gould. 



Geothermal Gradient in Michigan. A. C. Lane. 



Production of the X-Rays by a Battery Current. 

 J. Trowbridge. 



American Chemical Journal, May, 1900. 

 "Preparation and properties of the so-called 

 ' Nitrogen Iodide,' " by F. D. Chattaway and 

 K. J. P. Orton. Preparation from iodine mono- 

 chloride and ammonia ; ' The action of reduc- 

 ing agents upon nitrogen iodide,' by F. D. Chat- 

 taway and H. P. Stevens. Decomposition with 



formation in every case of hydriodic acid ; 

 ' On certain colored substances derived from 

 nitro compounds,' by C. L. Jackson and F. H. 

 Gazzolo ; ' The solution-tension of zinc in ethyl 

 alcohol,' by H. C. Jones and A. W. Smith; 

 ' Notes on lecture experiments to illustrate 

 equilibrium and dissociation,' by J. Stieglitz ; 

 ' A contribution to the knowledge of tellurium,' 

 by F. D. Crane. Method of purifying tellurium 

 and detecting small quantities of it ; ' The con- 

 stitution of gallein and coerulein,' by W. E. 

 Orndorif and C. L. Brewer ; ' Permanganic 

 acid by electrolysis,' by H. N. Morse and J. C. 

 Olsen ; ' On chlorine heptoxide,' by A. Michael 



and W. T. Conn. -, „ ^ 



J. Elliott Gilpin. 



SOCIETIES AND ACADEMIES. 



SCIENCE CLUB OF THE UNIVERSITY OF 



WISCONSIN. 



At the meeting of the Science Club of the 

 University of Wisconsin, held May 22d, Mr. J. 

 B. Johnson presented a paper on ' Recently im- 

 proved Methods of Sewage disposal.' The paper 

 was devoted to a consideration of the principles 

 underlying modern methods of treatment rather 

 than the details of construction of sewage plants. 

 The chemical and the bacteriological methods 

 of sewage disposal were contrasted and the for- 

 mer shown to be too largely an artificial process, 

 since it fails to make use of nature's effective 

 agents — the bacteria — which when afforded 

 suitable conditions change organic wastes into 

 soluble products and finally into the inorganic 

 nitrates and nitrites which constitute so largely 

 the food of plants. The chemical precipitation 

 plants were considered as belonging to a past 

 stage in the development of sanitary science, 

 and wherever installed are now looked upon as 

 an incubus to be got rid of as soon as pos- 

 sible. 



The combined septic tank and contact bed 

 method, which was first used at Exeter, Eng- 

 land, in 1896, and which is throughout a bac- 

 teriological method, Mr. Johnson regards as the 

 most satisfactory solution of the sewage problem. 

 The essential peculiarity of the method is that 

 it aflfords in the septic tank to which the sewage 

 is first conducted the ideal conditions for the 

 action of the anferobic bacteria whose function 



