216 ©E. H. Hall—Rotational Coefficients of Metals. 
physical properties, and any analogies thus suggested may be 
tested farther by more accurate and detailed investigations. — 
conditions remaining unchanged, by rise of temperature. It 
was a question of much interest whether the transverse current 
plate of hard rubber in such a manner as to extend the arms 
the limits of temperature to be employed it is more rigid than 
w. 
Aug. 2 the following results were obtained in the order give® 
* “Standard,” R,S. Williams & Co. 
