34- On Madame Gervais' Ne'-ji Method of Fermentation. 



you ; in addition to the pi'oofs tlierein contained, I can safely 

 assert, without the least tear of being proved incorrect, that 

 in a space of five hundred yards square of way-going work, the 

 ventilating medium would only have to travel a distance of 

 considerablv less than one-fourth that which it does in pillar 

 work ; and the velocity of the current of air is so much in- 

 creased, that it reduces the temperature of the mine so low 

 that the hewers are in general compelled to work with their 

 clothes on. 



I remain, Gentleuien, yours, &c. 

 Alnwick, Jan 20, ]S-2;J. A FuiEND TO THE PiTMEN. 



X. Ohserimtions on the Vinous Fermentation ; xcith a Descrip- 

 tion of cm Apparatus for the Improvement of the Process, ac- 

 cordijigto the Method invented Inj Madame Gervais. 



'" j "'HERE is scarcely a single production of the earth, whicli, 

 -*- when a})propriated to the use of man, is not so modified 

 or changed by various preparations, as to possess a different 

 property from that it containeil in its primitive state. 



Fruit and grain undergo decomposition, and a new recom- 

 position, before he uses them as food ; and until he applied art 

 to the juice of the grapes, they were suffered to decay on the 

 vines — but the ingeiniity of man has converted them into a 

 pleasant, wholesome, and lasting beverage. 



In those climates where the only substitutes for wine were 

 milk or water, the inhabitants are indebted to his invention for 

 malt liquor, a beverage which, although inferior to wine, is 

 not destitute of some of those qualities that render it so great 

 a desideratum. 



The process by which these new properties are pro- 

 duced, is termed the vinous fermentation ; it might, perhaps, 

 with more proprietj' be called the alcoholic or spirituous fer- 

 mentation, since it is a process by means of which all sacclia- 

 rine matters, whether they proceed from grapes, sugar-cane, 

 or malt, are decomposed and recombine to form alcohol. But 

 however wrong this denomination may be, we shall make use 

 of it in the following observations, as being well understood by 

 all classes. 



A vinous fermentation, to be perfect, requires very exact 

 proportions of mucilage and saccharine matter, so as to liave 

 the one just sufficient to destroy or attenuate the other; in 

 which case the result would be, if the operation had been pro- 

 perly conducted, a mixture of alcohol and water, differently 

 flavoured according to the materials from which it was pro- 

 duced, 



