6o 



V,. 



Table 30. 

 DIFFUSION. 



Inverse * values of z'/c= i — —7— / 



log X == log (2^) + logv''^^- ^ expressed in seconds. 

 = log 5 + log-v//^^. / expressed in days. 

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



. i = coefficient of diffusion.t 

 c = initial concentration. 

 V = concentration at distance x, time /. 



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

 of Sci. vol. III. 1897, p. 2S0. t For direct values see table 23. 



SviTHSONiAN Tables. 



