Simoun took it out with great care and, removing the burner, exposed to view the interior of the tank, which was lined with steel two centimeters in thickness and which had a capacity of over a liter.

Thus the diffusivity of common salt through water was found by Fick to be as small as 0.0000112 square centimeter per second; nearly 200 times as great as this is the diffusivity of heat through water, which was found by J.T. Bottomley to be about 0.002 square centimeter per second.

Centimeter at 67° F., too short .00008 cm.