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 Nociiluca, and its bearing on 

 the Status of the Cvstoflagellata (Haekel). 

 By Charles A. Kofoid 25 



Classification of Involutory Cubic Space 



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



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BAKNETT. The Preparation of Organic 

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CROWTHER. Molecular Physics. 2d Edi- 

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liOCHHEAD. Classbook of Economic Ento- 

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HATSCHEK. The Physics and Chemistry 

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REESE. Outlines of Economic Zoology. 194 

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MAXTED. Catalytic Hydrogenation and Re- 

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