comes in contact with saccharose the latter is forced to take up an additional atom of water and thus become glucose. The multiplication of the cells of yeast by budding is a process that may be easily watched under the microscope. If the temperature is kept between 75 and 90 degrees, one or more cells may be seen to arise in succession, or even at the same time, from a parent cell, and form themselves into short irregular chains. The vitality of yeast is dormant below 50, and is destroyed, as we should expect, at 140 degrees, for at that temperature nitrogenous matter begins to coagulate, The growth of yeast is checked it the solution of sugar is too dense, or if the quantity of alcohol is too large. Attempts have frequently been made by physiologists to account for these phenomena, but how and why carbonic acid and alcohol are substituted for sugar is still a mystery, and, like other mysteries connected with vitality, is likely so to remain. It has been ascertained that the weight of the alcohol and carbonic acid is nearly equal to the weight of the sugar which has disappeared. The slight difference is caused by the formation of other compounds that only appear in minute quantities. Some think that the glucose and other materials that form the food of the yeast plant penetrate the cell by osmose, and there, after undergoing transformation, we assimilated and converted into growing cells and tissues, while al the same time disassimilation is proceeding, the worn-out tissues ere changed into alcohol and carbonic acid, and are eliminated as excrementitious matter. This may be called the intra-cellular theory. Pasteur is of opinion that the vital action of the cell causes decomposition of the glucose, and that a portion of its oxygen penetrates the cell membrane and takes part in the process of assimilation, while the other constituents of the glucose are left outside free to arrange themselves into carbonic acid and alcohol. This is the extra-cellular theory. Which is correct? It remains for some one, perhaps a Woolhopian, to determine.
In this agricultural and woodland county there is abundant opportunity for the study, not only of the parasitic funguses, but of most others, and as our Field Club was constituted fer the purpose of observing and recording all facts connected with the Natural History of the district, it is to be hoped that some of our members will forthwith set up their microscopes and become students themselves. The facts observed at the time may often appear isolated and of little consequence, but subsequently by combination and further discovery they may become of the greatest value. Minute scientific research always precedes the application of science to industry, and, though little acknowledged, in at the present day performing a very important part in intellectual and industrial advancement, and will ere long effect great and unexpected changes.
The British Association.—The highly successful Dublin Meeting was brought to a close on August 21st, under the presidency of Sir William Spottiswoode, M.A. P.R.S., LL.D., D.C.L. &c. The total sale of tickets was 2,578. Next year's meeting will be held at Sheffield, commencing August 6th.
