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ROYAL MICROSCOPICAL SOCIETY,
RECORD OF HISTOLOGICAL RESEARCH
AT HOME AND ABROAD.
HENRY LAWSON, M.D., F.R.M.S.,
JULY 1, 1870.
1.—On Fungi and Fermentation. By JAMES BELL, F.C.S., &c.
, (Read before the Royal MICROSCOPICAL SOCIETY, June 8, 1870.)
PLATE LV. The first series of experiments to which I propose to refer is of a somewhat fundamental character, and relates to the behaviour of nitrogenized bodies in sugar solutions."
Albumen and Gluten.—It being generally understood that albumen and other nitrogenized substances are subject to spontaneous or natural fermentation, a series of experiments was instituted to determine the character or nature of the fermentation which nitrogenized bodies derived from different sources would give rise to.
The albumen of egg was first selected for experiment. To a solution of cane sugar a small quantity of egg albumen was added, and the sample was placed in a chamber which was kept at a temperature of 75o Fahr.
In a few days numerous minute transparent cells or spores were found to be diffused throughout the liquid ; these soon increased in size, but the largest were relatively much smaller than the cells of wort or wine ferment. The sample was examined on several occasions for alcohol, but great difficulty was experienced in the distillation on account of the frothing caused by the presence of the albumen. The largest quantity of alcoholf found in the liquid at any one time amounted to only about two-tenths per cent. .
The liquid gradually became acid, and in two or three weeks was found to be full of vibrios. At the end of forty-six and seventy-four days respectively the sample contained 1.02 and 2:16 per cent. of acid, and on the latter occasion it contained no alcohol whatever, the acidifying power having become greater than the alcoholic.
The cells contained a bright nucleus, sometimes situated in
* These experiments are still in progress, the albumen being subjected to various modes of treatment.
+ The alcohol in each case is given as absolute, and the percentage is estimated by volume.