r. Cyrus Adler, 



Smithsonian Institution. 



VOL. XXIII. 



JANUARY, 1907. 



Established by BENJAMIN SILLIMAN in 1818. 



THE 



AMERICAN 



JOURNAL OF SCIENCE. 



Editor: EDWAED S. DANA. 



ASSOCIATE EDITORS 



Professors GEOEGE L. GOODALE, JOHN TEOWBEIDGE, 

 W. G. FAELOW and WM. M. DAVIS, of Cambridge, 



Professors ADDISON E. VEEEILL, HOEACE L. WELLS, 

 L. V. PIES SON and H. E. GEEGOEY, of New Haven, 



Professor GEOEGE E. BAEKEE, of Philadelphia, 

 Professor HENEY S. WILLIAMS, of Ithaca, 

 Professor JOSEPH S. AMES, of Baltimore, 

 Mr. J. S. DILLEE, of Washington. 



FOURTH SERIES 

 VOL. XXIII— [WHOLE NUMBER, CLXXIIL] 



No. 133— JANUARY, 1907. 



NEW HAVEN, CONNECTICUT; jf\^ mm - l «W 



1907 I JAM 2 m 



\ 



THE TUTTLE, MOREHOUSE & TAYLOR CO., PRINTERS, 123 TEMPLE'StBEKK;. 



r—"""" 



, " 



t * <& 





Published monthly. Six dollars per year, in advance. $6.40 to countries in the 

 Postal Union. Remittances should be made either by money orders, registered 

 letters, or bank checks (preferably on New York banks). 



