_a._ (ALCOHOL, Ph. L. 1836.) Take of rectified spirit (sp. gr. 0·838), 1
gal.; chloride of calcium, 1 lb.; proceed as above, and distil 7 pints and
5 fl. oz. Sp. gr. of product 0·815. It contains about 7% of water, by
weight, and 5% by volume.
_b._ (ALCOHOL, Ph. D. 1826.) Rectified spirit, 1 gal.; pearl-ashes (dried
and still hot), 3-1/2 lbs.; mix, digest in a covered vessel, with frequent
agitation, for seven days; then decant the clear portion, and add to it of
chloride of calcium, 1 lb.; agitate to effect solution, and distil off the
spirit until the mixture in the retort begins to thicken. Sp. gr. of
product 0·810. It contains about 5% of water, by weight.
_c._ (Without distillation.) Rectified spirit is agitated, in a closed
vessel, with anhydrous carbonate of potash (prepared by heating the salt
to redness, and still slightly warm), until the powder sinks to the bottom
undissolved; the carbonate is then added in considerable excess, and the
agitation repeated at short intervals for some hours or even days; lastly,
after sufficient repose, the clear upper portion is decanted.--_Obs._ If a
clean spirit, and pure carbonate of potash (or at least one perfectly free
from caustic potash or any other impurity soluble in strong spirit), be
used, an alcohol sufficiently pure and free from water for many common
purposes may be thus obtained; otherwise the product contains a little
potassa, &c., which can only be removed by distillation. For some
purposes, however, this would not be objectionable. Sp. gr. about ·812.
[Illustration:
_A_, A bottle with two necks, the upper furnished with a
ground-glass stopper.
_B_, Loop of cord to hang the apparatus up by.
_C_, Bladder, containing spirit, filled by means of the bottle
_A_.
_D_, Neck of bladder accurately secured to the under neck of the
bottle _A_.]
III. (Soëmmering.--VARNISH-MAKER'S ALCOHOL.) The bladder of an ox or calf,
thoroughly cleansed from fat, and washed and dried, is nearly filled with
rectified spirit, and then securely fastened and suspended in any dry
situation, at a temperature of about 122° Fahr. In from six to twelve
hours, when the heat is properly maintained, the spirit is generally
sufficiently concentrated, and in a little time longer is rendered nearly
free from water (anhydrous), or of the strength of 96 to 98%.--_Obs._ The
same bladder will serve for more than one hundred operations. If not kept
very nearly full, a portion of the spirit escapes through the empty part.
To prevent this accident, a bottle with a double neck, of the shape
represented in the _engr._, may be employed; by which means the bladder
may be kept constantly full during the process. After the first or second
time of using, the bladder gives alcohol sufficiently pure for all
ordinary purposes. Before hanging the apparatus up, it is better to
enclose it in a coarse potato-netting, to prevent any accident arising
from the strain on the neck of the bladder. Soëmmering recommends both the
inside and outside of the dry bladder to be smeared over 2 or 3 times
with a strong solution of isinglass; but this is not necessary to the
success of the process.
IV. _Rectified Spirit._ (B. P. 1867.) _Spiritus Rectificatus._ Alcohol
with 16 per cent. of water; obtained by the distilling of fermented
saccharine fluids. Sp. gr. 0·838.
V. _Proof Spirit._ (B. P. 1867.) _Spiritus Tenuior._ Take of rectified
spirit, 5 pints; distilled water, 3 pints. Mix. Sp. gr. of product 0·920.
_Prop. of Alcohol._ Light, transparent, colourless; highly volatile and
inflammable, burning with a pale blue and smokeless flame; very mobile;
odour, agreeable; taste, strong and pungent; miscible in all proportions
with water, with the evolution of heat, and temporary expansion, but
ultimate condensation of the mixture, some hours elapsing before the union
is complete, and the normal temperature restored. The mixture has a higher
sp. gr. than the mean of its constituents; and this is greatest when 54
vols. of alcohol are mixed with 49·77 vols. of water, the resulting
compound measuring only 100 volumes. It absorbs water from moist air;
dissolves resins, essential oils, camphor, bitumen, soaps, sugar, carbonic
and boracic acid, iodine and the iodides, lime, ammonia, soda, potash, the
alkaloids, wax and spermaceti (when boiling), all the deliquescent salts
(except carbonate of potassa), and various other substances. It curdles
milk, coagulates albumen, and (in quantity) separates both starch and gum
from their mucilages. It boils, in the air, at 173° Fahr., when in the
anhydrous state. When diluted with water its boiling point rises in
proportion to the amount of water added. It boils, in vacuo, at 56° Fahr.
Every volume of boiling alcohol yields 488·3 vols. of vapour at 212° Fahr.
Its sp. gr. is 0·793811 at 60° Fahr., that of its vapour being 1·6133. It
has never been frozen; when cooled to -166° Fahr., it acquired the
consistence of castor oil, but did not solidify. It contracts by cold;
between -15° and +99° Fahr., this occurs with great regularity, at the
rate of ·00047 part of its volume for every degree of the thermometer. Its
evaporation, like that of ether, produces intense cold. The products of
its combustion are carbonic anhydride and water. It acts as a powerful
antiseptic on organic substances immersed in it, and is in consequence
extensively employed in the preservation of anatomical preparations. With
the acids it forms ethers.
_Phys. eff._ Alcohol is a narcotico-acrid poison. In small doses it
occasions excitement and intoxication; in larger ones, delirium,
somnolency, coma, apoplexy, and death. It acts as a violent nervous
stimulant, and, by abstracting water from the soft tissues of the stomach
and primæ viæ, destroys their organisation. It is alike poisonous to all
animals;--2 drs. will kill a dog. All strong spirits act in the same way,
the effect being proportionate to the state of concentration and the
quantity taken. On plants it acts as a rapid and fatal poison.
_Ant., &c._ Copious internal use of tepid water, with cold affusions to
the head and spine, and injection of cold water into the ears. In the
absence of vomiting, a strong emetic should be given, or the stomach-pump
used. Ammonia may be used as a stimulant, and, added to water just in
sufficient quantity to flavour it, is one of the best antidotes. The head
should be kept elevated, and bleeding had recourse to, if cerebral
congestion threatens.
_Tests in cases of death._ 1. The odour of the contents of the stomach and
ejected matters, and their ready inflammability. 2. The spirit may be
separated by digestion with water, filtration, the addition of carbonate
of potash, and distillation.
_Comp., &c._ Its per-centage composition is--
Dumas and Brande and Ure. sp.
Boullay. Ure. gr. 0·812.
Carbon 52·37 52·18 47·85
Hydrogen 13·01 13·04 12·24
Oxygen 34·61 34·78 39·91
------- -------- --------
99·99 100·00 100·00
This nearly represents 2 equivalents of carbon, 3 eq. of hydrogen, and 1
of oxygen. The atom of alcohol is now regarded as a multiple of these
numbers, and formed by the breaking up of one atom of grape sugar
(C_{13}H_{28}O_{11}) into 4 eq. of alcohol, 8 eq. of carbonic acid, and 4
eq. of water. It was formerly regarded as a compound of 1 eq. of olefiant
gas, and 1 eq. of water; but it is now generally viewed as HYDRATE OF THE
OXIDE OF ETHYLE (C_{2}H_{5}.HO), or a compound of ethylene and water
(C_{2}H_{4}.H_{2}O). Grape sugar alone yields alcohol; cane sugar, before
it undergoes the vinous fermentation, being first converted into this
substance by contact with the ferment.
_Purity._ The presence of water is shown by the specific gravity (see
ALCOHOLOMETRY); the absence of other foreign matter by the following
tests:--
1. Its colour and transparency is not affected by the addition of a little
colourless oil of vitriol (Liebig), or by a solution of nitrate of silver,
and subsequent exposure for some time to solar light (Vögel), unless
either essential oil or organic matter be present, when it assumes a
reddish tinge. 2. It should be neutral to test-papers, colourless, leave
no residue on evaporation, and be miscible, in all proportions, with water
and with ether. 3. Its boiling point should never be less than 170° Fahr.;
a lower temperature suggests the presence of wood spirits, or acetone, or
one of the ethers. To detect wood spirit (wood naphtha) see Nessler's
Test. For the reverse of this adulteration--the evasion of the duty by the
introduction of spirit, under the disguise of naphtha, turpentine,
&c.--see those articles.
4. The presence of water in alcohol may be detected, not only by the sp.
gr., but also by white anhydrous sulphate of copper burning blue when
dropped into it. 5. Potassium placed on alcohol does not take fire, unless
a considerable per-centage of water be present.
_Tests, &c._ 1. It may generally be recognised by its volatility,
inflammability, odour, taste, miscibility with water, power of dissolving
camphor and resins, and other qualities already described. 2. If a few
fibres of asbestos be 'moistened' with a saturated solution of bichromate
of potash in oil of vitriol, and exposed to the smallest possible portion
of hot alcohol vapour, it is almost instantly turned green, owing to the
formation of oxide of chromium. In practice, the asbestos may be inserted
in the neck of a retort, or even of a bulbed glass-tube containing a few
drops of the suspected solution, when the effect occurs as soon as
distillation commences. Ether and pyroxylic spirit produce a nearly
similar result; but the 'first' of these is distinguished from alcohol by
its not being miscible with water in all proportions; and the 'other' by
Nessler's Test; whilst both may be readily distinguished by their peculiar
and characteristic odour. 3. Dissolve 3 pts. crystallised carbonate of
soda in 10 pts. water. To this solution add 1 pt. of liquid to be tested,
and heat to about 160° Fahr. Lastly, add iodine in small pieces, till it
has entirely dissolved, and the liquid has become colourless. If alcohol
be present, iodoform will make its appearance on cooling, and sink to the
bottom in the form of a yellow powder. As a similar result is obtained
with wood spirit, this must be proved to be absent before applying this
test.
The only reliable method of proving that a sample is ethylic alcohol is
the production of ether, by acting on the suspected liquid with sulphuric
acid. See ETHER.
_Uses._ In the _arts_, alcohol is used by the varnish-maker to dissolve
resins; by the perfumer, to extract the odour of plants, and dissolve
essential oils, soaps, and other similar substances; by the pharmaceutist,
to prepare tinctures and other valuable medicinals; by the
instrument-maker, to fill the bulbs of thermometers required to measure
extreme degrees of cold; by the photographer, in the preparation of
collodion; by the chemist, in analysis, and in the manufacture of numerous
preparations; by the anatomist and naturalist, as an antiseptic; and by
the physician, for various purposes and applications as a remedy. It is
also frequently burnt in lamps, and in parts of the world where it is
inexpensive, it is employed in the manufacture of vinegar. Its uses, when
dilute, as in the 'spirituous liquors' of commerce, are well known. In
medicine, it is employed both concentrated ('alcohol,' 'rectified spirit')
and dilute ('proof spirit,' 'brandy,' 'gin,' &c.), as a caustic, irritant,
stimulant, tonic, &c. It has also been used in a multitude of other cases,
and has been applied to an almost infinite variety of other purposes.
[Illustration]
_Gen. commentary._ The selection of any one of the processes given above
for the preparation of alcohol must greatly depend on the convenience or
position of the operator. Chloride of calcium, and quick-lime, from their
powerful affinity for water, and easy application, are the hygrometric
substances most generally employed; but the processes involving the use of
the other substances and methods already noticed, have all of them
advantages under particular circumstances. Gay-Lussac has recommended the
use of caustic baryta instead of lime; and others have employed dry
alumina, as an absorbent of the water prior to distillation. Common proof
spirit may be concentrated until its sp. gr. falls to about 0·825, by
simple distillation in a water bath; at which sp. gr. it contains only
about 11% of water, by weight, and is then nearly as volatile as pure
alcohol.
A convenient apparatus for the preparation of alcohol, on the small
scale, is that figured in the _engr._, and which will be self-explanatory
to every one competent to use it. The tank (_i_) should be supplied with
ice-cold water; and the receiver (_g_) should be covered with cloths kept
continually wet with water of the same temperature. The capsule or basin
(_c_) is a water bath heated by the little gas furnace (_d_). On the large
scale, for commercial alcohol, a copper still, fitted with a glass
refrigeratory and receiver, is commonly employed.
By surrounding the capital of a still, or other like apparatus, by a water
bath kept at the proper temperature, the alcoholic richness or content of
the product may be regulated to the greatest nicety, for any desired
strength.
The different statements of chemical authors as to the boiling point,
specific gravity, &c., of alcohol, already noticed, may be referred to
their having either experimented with samples which have not been
absolutely anhydrous, or to their not having made the proper corrections
for temperature, and for the different materials of which their vessels
and instruments were composed--some probably having been made of glass,
and others of brass or some other metal. In some instances the differences
are more apparent than real, as in the _Tables_ by Tralles and Lowitz; in
the former of which water, at its lowest sp. gr., is taken as the
standard. Until recently, the only known source of alcohol was the
fermentation of saccharine solutions. Its production by synthesis, though
often attempted, is, however, erroneously said to have always failed. It
had long been employed as an occasional source of bicarburetted hydrogen
(olefiant gas) at a high temperature; but M. Berthelot succeeded in
reproducing it, from bicarburetted hydrogen, by agitating the latter, in a
closed vessel, with sulphuric acid and metallic mercury ('Journ. de Chimie
Med.,' 1855, p. 175); and Henry Flennel, nearly thirty years before M.
Berthelot's discovery, found that pure olefiant gas is absorbed by
agitation with concentrated sulphuric acid, with the formation of
sulphovinic acid, and that by subsequent dilution with water, and
distillation, alcohol passes over into the receiver.
=ALCOHOLATE.= _Syn._ ALCOHATE; ALCOHOLAS, L. A salt in which alcohol
appears to replace the water of crystallisation, as is the case with
certain chlorides, nitrates, &c. Some of them may be formed by simple
solution and crystallisation of the salt in alcohol. (Graham.) They are
all very unstable, being readily decomposed by water.
=ALCOHOLIC.= _Syn._ ALCOHOLICUS, L.; ALCOHOLIQUE, &c., Fr.; ALKOHOLISCH,
Ger. Pertaining to, containing, of the nature of, or made with, alcohol.
=ALCOHOLICA.= [L.] _Syn._ ALCOÖLIQUES, Fr.; WEINGEIST-VERBINDUNGEN, Ger.
In _pharmacy_, liquids containing, or preparations made with, alcohol, as
a characteristic ingredient.
=ALCOHOLISATION.= [Eng., Fr.] _Syn._ ALCOHOLISATIO, L.; ALCOÖLISATION,
&c., Fr.; ALKOHOLISERUNG, Ger. In _chem._ and _pharm._, the development of
the characteristic properties of alcohol in a liquid, or the use of it
either as an addition or a menstruum; also the act or process of obtaining
alcohol from spirit by rectification.
[Illustration]
=ALCOHOLOM'ETER= (-l[)o]m'-). _Syn._ ALCOHOL'METER (h[)o]l'-;
-h[)o]m'-[double-dagger]); ALCOHOLOMÉTRUM, L.; ALCOÖLOMÈTRE, ALCOÖMÈTRE,
ALCOHOLMÈTRE, &c., Fr. An instrument or apparatus used in alcoholometry.
Alcoholometers are simply 'hydrometers' adapted to the densities of
alcohol, either concentrated or dilute. Some of these, as BAUMÉ'S,
CARTER'S, &c., merely indicate the number of degrees corresponding to the
state of concentration of the liquid. Others, of a like construction, as
those of RICHTER (_a_), TRALLES (_b_), and GAY-LUSSAC (_c_), have their
stems so graduated as at once to indicate the proportion per cent. of
alcohol present, either by weight, or by volume, at some standard
temperature. (See _engr._) A third class, as those of the Abbé
BROSSARD-VIDAL, FIELD, &c. are essentially thermometers, with scales which
indicate the boiling points of spirits of different strengths, instead of
the common thermometric degrees; whilst to a fourth class belong the
alcoholometer of M. SILBERMANN, which is based upon the known rate of
expansion of alcoholic liquors by heat, expressed in alcoholometric
degrees; and that of M. GEISSLER, which depends on the measurement of the
tension of the vapour of the liquid, as indicated by the height to which
it raises a small column of mercury. In SYKE'S HYDROMETER, used by
officers of the Revenue, the scale of the instrument is enormously
extended by the use of movable weights, with each of which it becomes, in
fact, a separate instrument, adapted to a certain range of specific
gravities.
A very convenient alcoholometer for ordinary purposes (_d_) has been
lately produced by some of the instrument makers. It is of the usual form,
but its stem on one side exhibits the per-centage richness of the sample
in alcohol by volume; and on the other, the per-centage by weight. Thus,
both results may be obtained at one trial. This instrument is sometimes
called RICHTER'S ALCOHOLOMETER, in England. A further improvement, still
more recently introduced, is a similar 'double-scale' instrument, showing
the degrees of Sykes on one side, and carrying a small spirit-thermometer
in the bulb, to which a scale is fixed ranging from 35° to 82° Fahr.
=ALCOHOLOM'ETRY.= _Syn._ ALCOHOL'METRY (-h[)o]l'-;
-h[)o]m'-[double-dagger]); SPIRIT TESTING[double-dagger]; ALCOHOLME'TRIA,
L.; ALCOÖLOMÉTRIE, ALCOÖMÉTRIE, &c., Fr. In _chemistry_, the art or
process of ascertaining the richness of spirits in alcohol. In _commerce_,
the determination of the quantity of spirit of a certain strength, taken
as a standard, present in any given sample of spirituous or fermented
liquors. In England, this standard is called "proof spirit."
_Hist., &c._ The great importance of being able accurately to determine
the strength of spirits in the United Kingdom, on account of the high
duties levied on them, has induced the Government authorities, at various
times, to investigate the subject. In 1790, the matter was referred to Sir
C. Blagden, then Secretary to the Royal Society, who instituted an
extensive series of experiments to determine the real specific gravities
of different mixtures of alcohol and water. The results of his labours and
researches were put forward, with 'Gilpin's Tables,' in 1794, but no
practical measures appear to have been taken in consequence. In 1832 a
committee of the Royal Society, at the request of the Lords of the
Treasury, examined into the accuracy of the Tables, and the construction
and application of the instrument (SYKE'S HYDROMETER) now used by the
Revenue officers, on which they reported favorably, and declared that they
were sufficiently perfect for all practical and scientific purposes. The
errors introduced into calculations of the strength of spirits by these
tables were found to be quite unimportant in practice, and did not, in any
one instance, amount to unity in the fourth place of decimals. This method
adapts the specific gravity as the test of the strength of spirits, and is
founded on the fact that alcohol is considerably lighter than water, and
that (with proper corrections for condensation and temperature) the sp.
gr. regularly increases, or decreases, according to the relative
proportions in which the two are mixed.
Several other methods of alcoholometry have been proposed, founded
upon--the variations in temperature of the vapour of alcohol of different
strengths--the heat involved by its admixture with water--its dilatation
by heat--the tension of its vapour--the insolubility of carbonate of
potash in alcohol--its volatility, boiling point, &c. &c., the more
important and useful of which are noticed further on. The method adopted
by the Boards of Inland Revenue and Customs is, however, the one which is
almost exclusively employed in trade and commerce in Great Britain, not
only on account of its simplicity and correctness, but for the purpose of
the results exactly coinciding with the results obtained by the Revenue
officers.