154 
The apparatus in which the diffusion takes place, is represented 
in fig. 2; it consists of a glass beaker A of 2'/, liters of wide 
shape, placed on a tripod with double copper gauze. In the beaker 
on the wooden frame B, which surrounds the whole apparatus, are 
suspended the toluol regulator C and six test tubes D, one of which 
(D,) is filled halfway its height with the solution, the others (Da) 
with pure water. For the heating a Bunsen burner is used. At the 
beginning of a diffusion experiment seven glass cylinder holders /, 
each provided with a diffusion cylinder /'(/,—;) are placed in the 
test tube with the solution (D,), after the cylinders /’ of a diameter 
of 1°/, mm. and a length of about 2 em. have been filled with 
the solution by means of a pipette. When the whole apparatus has 
been brought to constant temperature, two or three of the cylinders 
(F,_3) from the test tube D, are successively immersed in another 
(D,) with pure water; this takes place by means of the tube G, 
which easily moves in the glass tube H,; in rest it is supported by 
the movable cork disk /. These three cylinders (#3) are taken 
out of the water immediately after the immersion. In the same way 
the eylinders (#4), which have been left in D, ave immersed 
