6o 



Table 31 . 

 DIFFUSION. 



Inverse * values of v /c ^ i — 



2 pt, 



V,. 



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



= log 5 + log\/^^. / expressed in days. 



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



i = coefficient of diffusion.! 

 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. i8g7, p. 280. •For direct values see table 24. 



Smithsonian Tables. 



