INFORMATION TO CONTRIBUTORS 
The Proceedings is the officiaj organ of the Academy for the publica- 
tion of brief accounts of important current researches of members of the 
Academy and of other American investigators, and for reports on the meet- 
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of science. The Proceedings will aim especially to secure prompt publication 
of original announcements of discoveries and wide circulation of the results of 
American research among investigators in other countries and in all branches 
of science. 
Articles should be brief, not to exceed 2500 words or 6 printed pages. 
Technical details of the work and long tables of data should be reserved for 
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and in exhibiting where practicable, the significance of the work for other 
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footnotes should be avoided. Indicate 'subject* for 'Contents.' 
Papers by members of the Academy may be sent to Edwin Bidwell Wilson, 
Managing Editor, Mass. Institute of Technology, Cambridge, Mass. Papers 
by non-members should be submitted through some member. 
Proof will be sent to authors only on their request, in order to avoid 
delay in publication. Authors are therefore requested to make final revisions 
on the typewritten manuscripts. The editors cannot undertake to do more 
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Copyright, 1917 f by the National Academy of Sciences 
