ALCOHOL 
before pumping the mash through the cool- 
ers into the fermenting cisterns. 
The apparatus and mashing process de- 
scribed are designed primarily for use in 
corn distilleries, but they may be adapted 
with but little change to use with pota- 
toes as a raw material. (1) 
Fermentation 
In older to minimize the chances tor 
souling and spoiling, the saccharine so- 
lution intended for fermentation is 
pumped to the fermenting cisterns as soon 
as possible after its preparation. Yeast 
which in the meantime has been pre- 
pared (2) separately in a small tub from 
a mash containing malt and either rye 
or potatoes, is added to it at once in a 
proportion varying between five and ten 
per cent. If necessary, water is added to 
fill the cisterns to within a few inches of 
the top, and the whole volume of liquid 
is thoroughly plunged or mixed. At this 
time the solution should contain between 
17 and 22 per cent of solids, as shown by 
a reading of 17 degrees to 22 degrees on 
the Balling saccharometer, and its tem- 
perature should be between 60 degrees 
and 65 degrees Fahrenheit. 
Within a few hours gas bubbles will be- 
gin to break the surface of the fermenting 
liquid, forming a constantly thickening 
cap of foam, and the whole mass of beer 
will rapidly come into vigorous motion. 
At the same time its temperature will be- 
gin to rise, and its specific gravity, as 
indicated by the saccharometer, will fall. 
According’ to the temperature, the kind of 
material fermented, and the strength of 
the yeast, fermentation will be complete 
within from 48 to 96 hours, as will be 
shown by the gravity and temperature 
ceasing, respectively, to fall and to rise, by 
the solution coming to rest and losing its 
foamy cap, and by cessation of the escape 
of gas bubbles. The fermented liquor, or 
distiller’s beer, is now said to be “dead” 
or “ripe,” and is ready for distillation. 
If the composition of the mash and the 
degree of fermentation are satisfactory, 
the beer should increase about 30 degrees 
(1) See Farmers’ Bulletin 410. p. 11 
(2) Detailed directions for making veast are 
given on p. 25 of Farmers’ Bulletin 410. 
ts 
~] 
Fahrenheit in tempeiature above the point 
at which it was set its gravity should 
fall almost to 0 degrees Balling, and it 
Should contain between six per cent and 
ten per cent of alcohol. 
Distillation 
The separation of alcohol from the fer- 
mented liquors in which it is formed is 
made possible by the fact that its boiling 
point, 173 degrees Fahrenheit, is lower 
than that of water by nearly 40 degrees 
Fahrenheit. On this account a mixture 
of alcohol and water boils at a lower tem- 
perature than water alone, and the vapors 
Which first arise from such a boiling mix- 
ture are richer in alcohol than the liquid 
itself. Thus, a mixture of aleohol and 
water which contains eight per cent by 
weight of alcohol, will boil at about 200 
degrees Fahrenheit, and will produce a 
vapor which contains approximately 43 
degrees of alcohol by weight. A liquor of 
the latter composition will in its turn 
boil at about 181 degrees Fahrenheit and 
will form a vapor containing about 68 
per cent of alcohol. When such mixtures 
are distilled all of their alcohol, mingled 
with more or less water, will pass over in- 
to the distillate, while a considerable pro- 
portion of the water still remains in the 
kettle of the still. It is possible, there- 
fore, even with stills of such simple type 
as are outlined in Fig. 1 and Fig. 2, to 
obtain ultimately a fairly strong alcohol 
by repeated distillation of the successive 
distillates. 
Such a still as is shown in Fig. 2 will 
produce in two successive distillations 
(singling and doubling) from 100 volumes 
of a beer containing approximately 10 per 
cent of alcohol about 37 volumes of a dis- 
tillate of 67 per cent strength together 
with about 23 volumes of weak distillates 
which can be saved for subsequent re- 
distillation. It would be impossible, how- 
ever, to make any quantity of a 90 per 
cent distillate with such an apparatus ex- 
cept by incurring an expense for fuel and 
labor which would far exceed the highest 
possible industrial value of the product. 
Fortunately it is possible so to con- 
struct a still that the requisite number 
of redistillations take place simultaneous- 
