ALCOHOL. —Adulterations.
152
liquors of different states of dilution, and under theinfluence of various degrees of temperature andpressure, enabling the diligent student to draw uptables of great accuracy and of less extent for refer-ence on all ordinary occasions. From what hasbeen said upon the properties of alcohol, in relationto its real specific gravity, it will be observed thatnone of the enumerated tables are strictly correct,since the density of absolute alcohol—to which allthe other densities bear a proportionate analogy—
stated in them, is considerably higher than thatassigned to it by chemists.
The annexed is a contraction of the foregoing tableof Gay-Lussac , showing the dilution per cent, inreducing liquors to a lower strength. The upperhorizontal column contains the per cent, of thestronger alcohol, and the vertical columns below, thebulk of water which is to be added to 100 volumesof it, to produce spirit of the quality indicated in theleft-hand column.
Desired strength inper cent.
100 vols. of alcohol of per cent, by voL
90
85
80
75
70
C5
CO
65
50
85
6-56
80
13-79
6-83
75
21-89
14-48
7-20
70
31-05
23-14
15-35
7-64
65
41-53
33-03
24-66
16-37
8-15
60
53-65
44-48
35-44
26-47
17-58
8-76
55
67-87
57-90
48-07
38-32
28-63
19-02
9-47
50
84-71
73-90
63-04
52-43
41-73
31-25
20-47
10-35
45
105-34
93-30
81-38
69-54
57-78
46-09
34-46
22-90
11-41
40
130-80
117-34
104-01
90-76
77-58
64-48
51-43
38-46
25-55
35
163-28
148-01
132-88
117-82
102-84
87-93
73-08
58-31
43-59
30
206-22
188-57
171-05
153-61
136-04
118-94
101-71
84-54
67-45
25
266-12
245-15
224-30
203*53
182-83
162-21
141-65
121-16
100-73
20
355-80
329-84
304-01
278-26
252-58
226-98
201-43
175-96
150-55
15
505-27
471-00
436-85
402-81
368-83
384*91
301-07
267-29
233-64
10
804-54
753-65
702-89
652-21
601-60
551-06
500-59
450-19
399-85
Adulterations of Spirituous Liquors and their Detection.—The sophistication of alcoholic liquors has beenpractised to give to many solutions containing verylittle spirit, the appearance and some of the physicalproperties which would be conferred by alcohol; andadulterations have also been practised with a view,as it were, of veiling the quantity of spirit.
The counterfeiting of strong alcoholic liquorsapparently as weaker spirit, or passing them off asquite a different liquid, was fostered in the wine-growing countries of the Continent, where largequantities of brandy were manufactured; and beforethe proper means of detection were at commandthe strongest brandy was often sold to the merchantsdisguised as ordinary wine, or a much weaker spirit,and by this means the Octroi duties were eluded.The imposition had long been practised after theintroduction of various hydrometric or alcoholometricscales for the determination of the amount of alcoholin spirituous liquors; for as most of these were onthe principle of the gravity test, various substanceswere added which would heighten the density, andmake it appear that the spirit was much more aqueousthan it really was. In other instances the spirit waspassed upon the excise as quite a different article,sometimes as a deodorising agent, while at othertimes it was made to assume the character of woodnaphtha. Expedients such as these have been prac-tised in this country; and in large towns where muchalcoholic liquor is consumed, drinks are frequentlysold to the public which are said to be alcoholic, butin reality contain little or no spirit. To defraud theexcise, sugar or other extractive matter is added tothe spirit to increase the specific gravity, and some-times wood-spirit, turpentine, pyroligneous acid,chlorine water, or other bodies possessing a strong
odour, are added to the liquor, and in this case it isrepresented as not being alcoholic.
The detection of these frauds is, for the most part,easy and expeditious. When sugar, extractive matter,pyroligneous acid, turpentine, &c., are suspected, itis only necessary to distil a portion of the liquid,and determine the density of the distillate by thehydrometer, or specific gravity bottle, and on referringto the corresponding gravity in either of the tablesalready given, under alcoholometnj , the correspondingvalue of alcohol is found. When a liquor is disguisedas wood naphtha, it is more difficult to determinethe amount of alcohol; distillation is in this caseineffectual, since the naphtha passes over at even alower temperature than the alcohol. The followingis the method recommended by Ure for the detectionof alcohol in wood or coal naphtha, or pyroligneousacid:—
A small quantity of nitric acid of specific gravityI-45 is first to be added to the spirit under examina-tion, and if alcohol be present it will immediatelyproduce an effervescence of nitrous ether (ethylnitrite, C 2 H 6 ,N0 2 ), which may be recognized as suchby its odour. The mixture is then treated with asolution of mercury in nitric acid—which is preparedby dissolving 100 grains of mercury in 1 fluid ounce ofacid, with the help of heat. Soon after this addition,and especially on raising the temperature, the mixturebegins to effervesce and to evolve thick etherealvapours; should the effervescence become too violent,it must be quelled by immediately withdrawing thefire, and cooling the vessel. A yellowish grey pre-cipitate falls down, which is mercuric fulminate(IIgC 2 N 2 0 2 ), and which should be immediatelyseparated by decanting or filtering the liquor fromit, washing the precipitate on the filter with a little