! ' I'.l'-i ' 



319 



With this view, an aliquot portion of each of them should be evaporated by a safety- 

 bath heat to a nearly concrete consistence, and then mixed with twice its volume of 

 strong spirit of wine. The truly saccharine substance will be dissolved, while the 

 starch and other matters will be separated ; after which the proportions of each may 

 be determined by filtration and evaporation. Or an equally correct, and much more 

 expeditious, method of arriving at the same result would be, after agitating the viscid 

 extract with the alcohol in a tall glass cylinder, to allow the insoluble fecula to subside, 

 and then to determine the specific gravity of the supernatant liquid by a hydrometer. 

 The additional density which the alcohol has acquired will indicate the quantity of 

 malt-sugar which it has received. The following Table, constructed by Dr. Ur, at 

 the request of Henry "VVarburton, Esq. M.P., chairman of the Molasses Committee 

 of the House of Commons in 1830, will show the brewer the principle of this im- 

 portant inquiry. It exhibits the quantity in grains' weight of sugar requisite to raise 

 the specific gravity of a gallon of spirit of different densities to the gravity of water 

 = 1-000. 



Specific Gravity of Grains' 'Weight of Sugar in the 



Spirit. Gallon Imperial 



0-995 -980 



0-990 1-890 



0-985 2-800 



0-980 3-710 



0-975 4-690 



0-970 5-600 



0-965 (5-650 



0-960 7-070 



0-955 8-400 



0-950 9-310 



The immediate purpose of this Table was to show the effect of saccharine matter in 

 disguising the presence or amount of alcohol in the weak feints of the distiller. But 

 a similar Table might easily be constructed, in which, taking a uniform quantity of 

 alcohol of 0'825, for example, the quantity of sugar in any wort-extract would be 

 shown by the increase of specific gravity which the alcohol received from agitation 

 with a certain weight of the wort, inspissated to a nearly solid consistence by a safety- 

 pan made on the principle of Dr. Ure's patent sugar-pan. (See SUGAB). Thus, the 

 normal quantities being 1,000 grains' measure of alcohol, and 100 grains by weight of 

 inspissated mash-extract, the hydrometer would at once indicate, by help of the Table, 

 first, the quantity per cent, of truly saccharine matter, and next, by subtraction, that 

 of farinaceous matter present in it. 



The advance of the arts is gradually assuming a character which will no longer 

 permit any manufacturer to neglect the assistance of science ; and those who first take 

 advantage of the power of knowledge will assuredly leave their fellow-labourers 

 behind. From being an uncertain and hazardous operation, brewing must ere long 

 become a fixed and definite principle based upon facts well understood, and capable 

 of perpetual repetition and reproduction at will. To sum up briefly the general details 

 of ale-brewing, we may state, that, for most kinds of ale, the attenuation in the first 

 instance should bo finished in from six to twenty-one days, according to the strength 



