SCIENCE— ADVERTISEMENTS 



OUGHTRED'S 



Mathematical Symbols 



By FLORIAN CAJORI 



RECENT PUBLICATIONS 



A List of Oughtred's Mathematical Symbols 



with Historical Notes. By 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 by 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 



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