June 25, 1915] 



SCIENCE 



945 



is to be dealt with in a forthcoming volume in 

 the Cambridge Public Health Series by Dr. 

 W. E. Adeney. This also will be welcomed by 

 American readers. Another omission is that 

 ■of the process so largely and successfully used 

 in New England, the process of intermittent 

 ■sand-filtration. 



The author's treatment of septic tanks and 

 their limitations is extremely interesting. He 

 ■describes not only the hydrolytic tank by Dr. 

 Travis and the Imhoff tank, but also the 

 Kremer and Eieldhouse tanks, which are not 

 :as well known in this country. Greater at- 

 tention is given to the disposal of sludge than 

 in many books and the subject of trade wastes 

 and their disposal is also treated at consider- 

 .able length. 



G. C. Whipple 



Haevaed University 



PBOCEEDINGS OF TBE NATIONAL ACAD- 

 EMY OF SCIENCES 

 (number 5) 

 The fifth number of volume 1 of the Pro- 

 ■ceedings of the National Academy of Sciences 

 contains the following articles: 



1. Some ProMems in Stellar Photometry : Joel 

 Stebbins, Astronomical Observatory, Uni- 

 versity of Illinois. 



This was a part of the address of Mr. Steb- 

 Tsins as Draper Medallist before the Academy 

 -on April 20, 1915. It contains a number of 

 suggestions as to probably fruitful methods 

 and problems of stellar research with the aid 

 of the photometer. 



2. The Composition of Brachiopod Shells: F. 

 W. Claeke and W. C. Wheeler, United 

 States Geological Survey, Washington. 

 The authors present an investigation to 



■determine, more definitely than hitherto, just 

 what substances are contributed by each group 

 •of marine invertebrates to the marine sedi- 

 ments, with a special reference to the forma- 

 tion of magnesian and phosphatic limestone. 



S. On the Occurrence of the Line i,686A and 

 the Related Series of Lines in the Spectra 

 of the Planetary Nehulcs: W. H. Wright, 

 Lick Observatory, University of California. 



The line 4,686A and related series of lines as 

 observed in the spectra of heavenly bodies, and 

 more recently obtained from laboratory sources, 

 have played an important role in some theories 

 of the constitution of atoms; and Mr. Wright 

 here presents a number of observations con- 

 cerning the different forms in which line 4,686 

 occurs in nebute. In particular, he observes 

 that it appears either as a narrow line in the 

 nebulosity or as a broad band in the nucleus; 

 rarely in both forms. 



4. The Nature of Nerve Conduction in Cas- 

 siopea: A. G. Mayer, Department of Marine 

 Biology, Carnegie Institution of Washing- 

 ton. 



The nature of nerve conduction appears to 

 be some chemical reaction involving the ad- 

 sorbed sodium, calcium and potassium cations, 

 and its rate is proportional to the concentra- 

 tion of these absorbed ions, and is thus a sur- 

 face effect. The work, therefore, supports 

 other recent work by Tashiro and Lillie. 



5. A New Canonical Form of the Elliptic 

 Integral : B. I. Miller, Department of Math- 

 ematics, Johns Hopkins University. 



A new canonical form of the elliptic integral 

 is suggested which has the advantages over the 

 Klein-Bianchi form that it is simpler in form, 

 unique and invariant under certain trans- 

 formations. 



6. The Structure of Complex Atoms and the 

 Changes of Mass and Weight involved in 

 their Formation: W. D. Harkins and E. D. 

 Wilson, Kent Chemical Laboratory, Uni- 

 versity of Chicago. 



This is a contribution to a subject at present 

 very widely discussed as to the nature of the 

 atom. The authors find that it is possible to 

 construct the various atoms of low atomic 

 weight out of the helium and hydrogen atoms. 

 The departure of the atomic weights from 

 integral values on the hydrogen basis is attrib- 

 uted to the fact that the interference of the 

 electric charges in the nucleus of the helium 

 atom produces a diminution of the electro- 

 magnetic mass sufficient to lower the atomic 

 weight; and close coincidence of the atomic 

 weights with integral values on the oxygen 

 basis is taken to indicate that the diminution 



