Diffusion of Hydrogen through Hot Platinum. 1g 
the numbers in Table I. yield the following values of this 
ratio:— 
és, ie me. LOO, | 
ecu 576 141 44 | 
856 TAG 139 3°09 
1136 99>. | 14h 2°29 
| 
The values of t,—t, above are not quite constant, but are 
sufficiently so to demonstrate the above property. In this 
respect, the rate of diffusion resembles the vapour-pressure of 
a liquid. The relation between the quantity (Q) of hydrogen 
Fig. 2. 
Ota", 
0 
500 600 700 800 900 1000 1100 1200 
Temperature Centigrade. 
diffusing through the tube per second, on the one hand, and 
the pressure and temperature on the other, is made still 
clearer by means of the two accompanying diagrams 
(figs. 2 & 3). 
