893 DISTILLATION. 
very eafily in the diftillation of fpirits from corn ; yet it will be neceflary to introduce a thermometer into the 
one might think that this fault would not take place in box c, which is open without; for, as the fpirit of wine 
this apparatus to the fame extent as in the common way boils at 165 degrees of Fahrenheit, and water requires 
of applying the fire. The grains, on account of their 212, the heat of the boiling water will be fufficient to 
gravity, fink to the bottom,' on which, in the common raife the watery particles, though the fluid in the velfel 
Hill, the fire can exercife the ftrongeft adtion ; whereas will not acquire that temperature. It will be mod ad- 
in this Hill the bottom of the velfel is expofed to the vantageous to maintain the heat till the thermometer in- 
leaft heat, and, confequently, is better fecured from dicates from 170 to 175 degrees. If this degree of heat 
burning. It however cannot be denied, that by the heat be continued without fullering it, by carelelfnefs, to be 
of the furnace the burning fometimes may take place, raffed higher, the fpirit of wine, by the firft rectification, 
efpecially when fufficient caution is not obferved in ma- will be pretty pure, and free from water ; but it is necef- 
naging the fire. Might not this fault be remedied by fary, towards the end of the diftillation, to ftrengthen a 
coating the furnace with a flight covering of flightly little the degree of heat, as, without this precaution, the 
burnt clay or of plafter or gypfuin, which, as they can 
hold a great deal of water, would guard againft burning 
without interrupting much the adtion of the heat on the 
fluid? 
For the purpofe of reBifying the fpirit after it is dif- 
tilled, another apparatus is provided, almoft the fame as 
the above, only that during diftillation the fire cannot aft 
immediately on the fluid, but the fluid receives the heat 
neceflary for its converfion into fleam through the me¬ 
dium of water brought to a ftate of ebullition by the fire, 
and called, reBification by the water-bath. As, in diftilling 
fpirit of wine made from corn fpirit* the degree of heat 
cannot be fo accurately graduated as to prevent the riling 
of aqueous vapour, which again renders the diftilled li¬ 
quor impure, the advantageous employment of the wa¬ 
ter-bath was long ago thought of, by which the higheft 
poftible degree of heat fliort of that of boiling water can 
be obtained. Demachy propofed for this purpofe a cop¬ 
per kettle filled with water, in which the ftill was fuf- 
pended. But it may be readily feen, that a much larger 
furnace than common would be neceflary for this purpofe, 
and confequently a larger proportion of fuel ; but at the 
fame time that this apparatus is deftined to promote a 
faving of fuel, it is in nothing inferior to that propofed 
by Demachy. 
Fig. 3, reprefents this apparatus without the cooling 
part, which is entirely the fame as that already defcribed 
for Ample diftillation. A is a wooden velfel bound round 
with iron hoops, to the bottom of which is fattened the 
before-defcribed furnace e, with the afti-hole f, and the 
tube which ferves for introducing the fuel, only that it is 
not applied to the middle, but to the fide, of the velfel. 
The tube deftined to afford a paffage to the air, and 
to convey off the fmoke, does not conlift, as in the former 
apparatus, of three pieces, but of one whole, which does 
not pafs direftly through the fide oppofite to that where 
the fuel is fupplied, but extends at mod only to two- 
thirds of the width of the velfel, where, by means of a 
knee, it turns up, and, by a fecond knee, is brought back 
to the other fide. The whole furnace occupies, in gene¬ 
ral, only one-half of the bottom of the velfel, and is equal 
in'height to only one-fourth of that of the velfel. Over 
the furnace there is a copper box b, which occupies 
nearly two-thirds of the diameter of the velfel, as if in 
a femicircle, and completely covers the furnace as well 
as the tubes. Its height is about two-fevenths of that- 
of the velfel. Strictly fpeaking, it has only one fide; 
lor the reft are formed by the tides of the velfel. From 
the upper part of it there proceeds a fmaller longilh box, 
c, which paffes through the fide of the velfel, and the 
upper part of which above the velfel is open. In the 
laft place, on that part of the bottom of the velfel covered 
by the box there is a cock, h, which ferves for conveying 
oft the water. The remaining parts of the apparatus are 
not different from tliofe of that defcribed under fig. 2. 
When reftification is to be performed, let the box be 
completely filled with water, through the part that pro¬ 
trudes beyond the velfel ; and when the water has been 
brought to a ftate of ebullition by the furnace, it can 
communicate to the fpirit the heat neceflary for convert¬ 
ing it into vapour. If it be defired to carry on the ope¬ 
ration with greater accuracy for fpirit of wine or alcohol, 
2 
laft fpirit of wine that palfes over would be rendered im¬ 
pure by more or lefs water. 
In common, corn fpirit has an unpleafant fmell and 
tafte, the primary caufe of which is carelefs management 
during the firft diftillation. The fault chiefly lies in the 
fermentation of the walh being too long continued. In 
general, the diftillation is not begun till the fermenting 
liquor throws up no more bubbles, and Ihews itfelf per- 
feftly tranfparent under the feum : but it has been con¬ 
firmed by feveral experiments, that the corn fpirit is ob¬ 
tained ftrongeft, and in the greateii abundance, when the 
mixture is fubjefted to diftillation in its higheft degree 
of fermentation. If the fermentation be fuffered to ob¬ 
tain its utmoft term completely, a quantity of vinegar 
will be formed, which not only contributes to give the 
liquor an unpleafant tafte, but actually occafions a conli- 
derable lofs of the faccharine matter neceflary for the pro¬ 
duction of the fpirit. 
It is too commonly found, in diftillations in the large 
way, that the worm or fpiral which palfes through the 
cooling tub or refrigeratory, does not prefent fur fade fuf¬ 
ficient to the cooling medium, to give adequate difpatch 
to the operation. To obviate thisdefedf, Mr. F. Atlee, 
diitiller, at Wandfvvorth, in Surrey, has conlirudteda re¬ 
frigerating velfel with an additional fpiral tube, for which 
invention he obtained letters patent in February 1797 ; and 
lie deferibes and figures the velfel and its fpiral tubes thus: 
The figure reprefents a feclion of the refrigerating vef- 
fel, 
