INFORMATION TO CONTRIBUTORS 
Tun Proceedings is the ofl&cial organ of the Nationai. Academy op 
Sciences and of the National Research Councii. for the publication of 
brief accounts of important current researches of members of the Academy 
and of the Council and of other American investigators, and for reports 
on the meetings and bther activities of the Academy and of the Council. 
Publication in the Proceedings will supplement that in journals devoted 
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to secure prompt publication of original announcements of discoveries 
and wide circulation of the results of American research among investi- 
gators in other countries and in all branches of science. 
Articles should be brief. The viewpoint should be comprehensive 
in giving the relation of the paper to previous publications of the author 
or of others and in exhibiting, where practicable, the significance of the 
work for other branches of science. Elaborate technical details of the 
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precise in making clear the new results and should give some record of 
the methods and data upon which they are based. 
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International Catalogue of Scientific Literature, viz., name of author, 
with initials following (ordinarily omitting title of paper) , abbreviated name 
of Journal, with place of publication, series (if any), volume, year, inclusive 
pages. For example: Montgomery, T. H., /. Morph,, Boston, 22, 1911 
(731-815); or. Wheeler, W. M., Konigshurg, Schr. physik. Ges., 55, 1914 
(1-142). 
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Wilson, Managing Editor, Mass. Institute of Technology, Cambridge, 
Mass. Papers by non-members should be submitted through some 
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