Spirit of wine is contained in many mixtures, and for the purpose of ascertaining how much alcohol may be in wine, or any other liquid, a hydrometer is used (fig. 432). This instrument consists of a glass tube with a bulb at the end. It is put into water, and the place the water “cuts” is marked by a line on the stem, and called zero 0°. Spirit of wine has less specific gravity than water, so in absolute alcohol the instrument will sink lower than in water, and will descend to a point which is marked 100. In any mixture of alcohol and water, of course the hydrometer will rise or sink between the extreme points accordingly as the mixture may contain less alcohol or more. So a scale can be furnished. The instrument, as described, was invented by MM. Gay-Lussac and Tralles, and called the “percentage” hydrometer. There are many other instruments marked in a more or less arbitrary manner. We append a comparative table of a few hydrometers. (See [page 420].)
Ether, or sulphuric ether, is a mixture of spirits of wine with sulphuric acid, and distilled. It loses water, and the product is ether, which is volatile, and transparent, with a peculiarly penetrating odour. It will not mix with water, and if inhaled will produce a similar effect to chloroform.
Comparative Table of Hydrometers.
| Specific Gravity. | Percentage Volume (Tralles). | Percentage Weight, at 60° F. | Degree, according to Cartier. | Degree, according to Beck. | Degree, according to Baumé. |
|---|---|---|---|---|---|
| 1·000 | 0 | 0 | 10 | 0 | 10 |
| 0·991 | 5 | 4·0 | ... | ... | ... |
| 0·985 | 10 | 8·0 | 12 | ... | ... |
| 0·980 | 15 | 12·1 | ... | 3 | 13 |
| 0·975 | 20 | 16·2 | ... | ... | ... |
| 0·970 | 25 | 20·4 | 14 | 5 | ... |
| 0·964 | 30 | 24·6 | 15 | 6 | 15 |
| 0·958 | 35 | 28·9 | ... | ... | 16 |
| 0·951 | 40 | 33·4 | ... | 9 | 17 |
| 0·942 | 45 | 37·9 | 18 | ... | ... |
| 0·933 | 50 | 42·5 | ... | 12 | 20 |
| 0·923 | 55 | 47·2 | 21 | 14 | ... |
| 0·912 | 60 | 52·2 | ... | 16 | 24 |
| 0·901 | 65 | 57·2 | 24 | 19 | ... |
| 0·889 | 70 | 62·5 | 27 | ... | 28 |
| 0·876 | 75 | 67·9 | ... | 24 | ... |
| 0·863 | 80 | 73·5 | 30 | 27 | 32 |
| 0·848 | 85 | 79·5 | 35 | 30 | 35 |
| 0·833 | 90 | 85·7 | ... | 34 | 38 |
| 0·815 | 95 | 92·4 | 40 | 38 | 42 |
| 0·793 | 100 | 100·0 | 44 | 44 | 48 |
Chloroform is transparent, and will sink in water. Diluted alcohol with hypo-chloride of lime, will produce it. When inhaled, chloroform produces a pleasing insensibility to pain, and is useful in surgery.
A certain compound of alcohol with mercury dissolved in nitric acid will cause decomposition, and white crystals will eventuate. These compound crystals are termed fulminating mercury.
We must now pass rapidly over the few remaining subjects we have to notice, such as fats and soaps, wax, oils, etc.
Fats are of the greatest use to man, particularly in cold climates, for upon them depends the heat of the body. Fatty acid, if liquid, is known as oleic acid; if solid, stearic acid. Soaps are compounds of fatty acids. Many “fats” are consumed as food, others as fuel or for lighting purposes, in the shape of oils. Such oils are not primarily useful for burning. Petroleum and other mineral oils are found in enormous quantities in America.