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Vol. X, No. 2 



JANUARY, 1905 



The Policy of France toward the Mississippi Valley in 

 the Period of Washington and Adams. Frederick 

 Jackson Turner. 



Improvising a Government in Paris in July, 1789. 



Henry E. Bourne. 



The Treaty of a Guadalupe-Hidalgo. Jesse S. Reeves. 



Materials in British Archives for American Colonial 

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CVII. February, 1905. 



TABLE OP CONTENTS. 



On the Differential Transformer. A. Trowbridge. 



Heat of Vaporization of Liquid Air. 



R. C. Fenner and F. K. Richtmyer. 

 Tlie Coefficient of Expansion of Nickel at its Critical 

 Temperature. H. M. Randall. 



The Velocity of Sound. Thos. C. Hebb. 



Tlic Arc Ina IMaguetic Field. C. D. Child. 



Apparatus to Illustrate Pressure of Sound Waves. 



R. W. Wood. 



American Physical Society, Minutes of the twenty- 

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