IM ^fr 



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S ^ 3è ft » 



THE 



JOURNAL 



OF THE 



COLLEGE OE SCIENCE, 



IMPERIAL UNIVERSITY OF TOKYO, 



Vol. XXXI. 



^ ^ ^ ® :^ -^ PP ^f 

 PUBLISHED BY THE UNIVERSITY, 



TOKYO, JAPAN. 



1911. 



MEIJI XLIV. 



