SCIENCE— ADVERTISEMENTS 



OUGHTRED'S 



Mathematical Symbols 



By FLORIAN CAJORI 



RECENT PUBLICATIONS 



A List of Oughtred's Mathematical Symbols 



with Historical Notes. Bj' Florian Cajori .25 



On the History of Gunter's Scale and the 

 Slide Rule during the Seventeenth Cen- 

 tury. By Florian Cajori 35 



Treatment of Harmonics in Alternating Cur- 

 rent Theory b}' means of a Harmonic Al- 

 gebra. By Abraham Press 1.00 



A New Morphological Interpretation of the 

 Structure of Noctiluca, and its bearing on 

 the Status of the Cystoflagellata (Haekel ). 

 By Charles A. Kofoid 25 



Classification of Involutory Cubic Space 



Transformations. By F. M. Morris ... .25 



The University of California Press 



Berkeley, California 280 Madison Ave*, New York 



The Human Side of 

 Botany 



You expect a college botany to present 

 a well-rounded , scientific course Dens- 

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 of immediate human interest. "Gen- 

 eral Botany " is illustrated with ori- 

 ginal scientific drawings and photogra- 

 phs of unusual beauty. Densmore's 

 "General Botany" may be obtained 

 from 



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E. F. NORTHRUP, PRESIDENT AND TECHNICAL ADVISER 



Cat. No. 3000 



