ie THE EVOLUTION OF LIFE 
I have ascertained that boiling a quantity 
of fluid briskly in a vessel with a very narrow 
aperture very distinctly raises the boiling point. 
This I discovered by introducing a small maximum 
registering thermometer into one of the experimental 
retorts containing an ounce of a hay infusion, draw- 
ing out its neck so as to leave only the usual narrow 
orifice, and then boiling the fluid briskly for five 
minutes. The thermometer was an accurate one 
made specially for me by Hicks of Hatton Garden ; 
its bulb was kept about three quarters of an inch 
away from the glass, and yet at the end of five 
minutes it was found to register 103°33° C. (218° F.). 
With a larger quantity of fluid, and the same small 
orifice, especially when the heating was continued 
over a prolonged period, as in the preparation of the 
tinned meats and vegetables, the temperature of the 
contents may well have been raised to about 225° F. 
(1074 C.). . 
Much would depend upon the smallness of the 
aperture together with the bulk of the fluid, as 
was shown by a letter in the same number of 
Nature (July 10, 1873) from W. N. Hartley, who 
said :— 
‘“T sealed a tube on to a flask of about 100 c.c. 
capacity at right angles to the neck, and drew out 
the end so as to form a capillary orifice. About 30 
1 See Nature, July 10, 1873. A similar elevation of temperature, to 
a certain extent, would occur in experiments conducted after the 
manner of Schwann ; or when flasks with long, narrow and bent necks, 
or others whose necks were plugged with cotton wool, were employed, 
as was done by Pasteur. The temperature in all these cases would 
certainly be raised to a point over 212° F. 

