3io 
Notes . 
similar solution of the unheated albumin, both became opalescent 
at a temperature of 6o°C., and both were completely coagulated 
at 62° C. 
It thus appears that, if precautions are taken to ensure appropriate 
desiccation, it is possible to heat albumin for, at any rate, thirteen 
hours to a temperature varying between 102-110° C. without pro¬ 
ducing any obvious change in its ultimate molecular (or micellar?) 
structure. It made no difference to the result whether the heat was 
gradually or rapidly applied. Thus, in one experiment, the tem¬ 
perature was raised from 50° C. to io 3°C. in fifteen minutes, and in 
other examples the flask was withdrawn from the hot bath, cooled, 
and suddenly reimmersed. How much higher the temperature could 
be raised without producing an obvious effect, I am not prepared to 
say; nor did I investigate the action (if any) which might possibly be 
produced by a much longer exposure to heat within the limits already 
mentioned. This formed no part of my object, which was primarily 
to try to get a point of comparison between the complex seed and the 
simpler but still very complex proteid. 
Other experiments were made in order to test the sensitiveness of 
the albumin to small quantities of moisture. 
For this purpose, two flasks attached to drying-tubes were used, one 
of them serving for a control experiment, and remaining unopened 
until the end. The other was opened three times, and a small sample 
taken out each time. By this means the ordinary air of the room 
obtained complete access to the albumin. The duration of the experi¬ 
ment was ten hours. The first sample was withdrawn after the flasks 
had been heated to io2°C. for three hours; it dissolved and coagu¬ 
lated normally. A second sample was withdrawn after three hours 
more, and it was found that whilst it dissolved and became opalescent 
on heating to 6o° C., the coagulation change did not at once set in, 
but the opalescent solution became more milky and of a deeper fog- 
yellow by transmitted light, finally coagulating at about 68° C. A 
third sample taken out at the close of the experiment (i.e. four hours 
after the last opening of the flask) also dissolved, became slightly 
opalescent at about 64° C., but did not coagulate even at 90° C., 
although the opalescent milkiness became very pronounced. Viewed 
by transmitted light, the solution was translucently yellow. Even 
boiling failed to produce anything which could be fairly termed a 
coagulum. It appeared probable that the admission of watery vapour 
