VOL. I MAY, 1921 



Established by BENJAMIN SILLIMAiS^-m 1818. 



i> MAY - H \'^^ 





THE ■^**' 



AMERICAN 



JOURNAL OF SCIENCE. 



Editor: EDWAED S. DAl^A. 



ASSOCIATE EDITORS 



Professors WILLIAM M. DAVIS and KEGINALD A. DALY, 



OF Cambridge, 



Professors HORACE L. WELLS, CHARLES SCHUCHERT, 



HERBERT E. GREGORY, WESLEY R. COE and 



FREDERICK E. BEACH, of New Haven, 



Professor EDWARD W. BERRY, of Baltimore, 



Drs. FREDERICK L. RANSOME and WILLIAM BOWIE, 



OF Washington. 



FIFTH SERIES 



VOL. I— [WHOLE K UMBER. CCI]. 

 No. 5 -MAY, 1921. 



NEW HAVEN, CONNECTICUT. 



1921. 



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