6o 



TABLE 30. 

 DIFFUSION. 



Inverse * values oiv/c=i -^ j 



log x = log (zq) + \og\/kt. t expressed in seconds. 

 = log 5 + \og\Ski. t expressed in days. 

 = log 7 + log \/kt. " " years. 



f k = coefficient of diffusion, t 

 c = initial concentration. 

 v = concentration at distance x, time t. 



Kelvin, Mathematical and Physical Papers, vol. III. p. 428 ; Becker, Am. Jour. 

 of Sci. vol. III. 1897, p. 280. t For direct values see table 23. 



SMITHSONIAN TABLES. 



