360 



PROCEEDINGS OF THE AMERICAN ACADEMY. 



Figure 2. The curves show the final temperatures on the axis (OS) of 

 a circular disk of given thickness (c) and of diameter d, when one face is kept 

 at the temperature 100° and the other face and the rim at 0°. In A, B, C, D, 

 and E, the diameter has the values £ c, c, § c, 2 c, 3 c, respectively. 



Jefferson Physical Laboratory, 

 Cambridge, Mass., 



December, 1909. 



