36 On Madame Clervais' AVic' Mel had of Fcrmoiiatiuiu 



contact with the cold interior surlace of the cone : and being 

 tliereby converted into h(juid, trickles dtswn the inside of the 

 condenser, and through a long pipe is returned into the fer- 

 menting liquor. 



By the application of this apparatus, a considerable portion 

 of alcohol, which has been hitherto suiFered to escape in the 

 form of vapour, along vv^ith the non-condensable guses, is con- 

 densed and returned into the liquor ; and the non-condensable 

 gases are carried off by a pipe, which, proceeding from the 

 interior lower part of the cone, and running up the inside of 

 the cylinder in the cold water, passes out through the side, 

 and the end is inunersed some dejith below the surface of wa- 

 ter contained in a separate vessel, permitting the gases to 

 escajie, but still under a certain degree of pressure, the object 

 of which is, to coiifine the aicoiiolic steam and gas within the 

 cone, and allow them a sufhcient time to cool and condense. 



To persons in the least acquainted with chemical opera- 

 tions, it would be useless to dwell oii the merits of this api)a- 

 ratus ; they v.-ill at once see how beneficial it would prove to 

 any liquid that has to undergo tlie vinous fermentation in any 

 stage of its manulacture; but to those v. ho are not so conver- 

 sant in the principles and causes of these operations, they will 

 require to be pointed out. 



To obtain a good fermentation, as complete a decomposi- 

 tion of the must or wort, and as perfect a recomposition of 

 alcohol as possibk^, are the great objects to be obtained. 

 To acquire the former, three re([uisites are necessary; fluidity, 

 heat, and motion. The latter ; density, coolness, and tran- 

 (juillity. 



Let us examine each of diese sej^arately: first, of fluidity. 



The specific gravity of the liquid, most eligible to produce 

 a good fermentation, is between 1-020 and l-i40, or eighteen; 

 and one hundred and thirty-two pounds by Dicas's improvecl 

 saccharometer, made l)y Joseph Long, No. '20, Little Tower- 

 street, London. Below eighteen jiounds of real extract per 

 barrel, the li(iuid is too thin to produce a proper fermentation, 

 and above one humlrcd and thirty-two pounds it is too thick; 

 but supposing the specific gsavity of the must or wort to be 

 correct, it may be carried beyond a proper dilatation by too 

 nnich heat, or congealed to loo great a consistency by exces- 

 sive cold; consecjuently eitlier a thunder-storm or hard frost 

 will derange the ojieration, and are equally injurious to fer- 

 mentation. Any method, therefore, that will ensure an even 

 temperature nuist be of great importance; and such a method 

 is obtained by applying tlic apparatus already described, since, 

 by preventing the access of alino>jiheric\iir, the sudden 



(•liauK'ei 



