Popular Science Monthly/Volume 19/June 1881/Natural Production of Alcohol
M. A. MÜNTZ, of the French National Agronomical Institute, announces that he has discovered traces of alcohol as a natural product in cultivated soil, rain-water, sea and river-water, and the atmosphere. He has detected the product, it is true, only in the most
infinitesimal quantities, but he has established the fact of its existence by analyses which are at once simple, clear, and convincing.
He has submitted to distillation some fifteen or twenty litres, or quarts, of snow-, rain-, or sea-water in the apparatus which is represented in Fig. 1. This apparatus consists of a milk-can, B, which is made to serve as a boiler, in which the liquid to be distilled is put. The vapors disengaged by the heat pass through a worm about thirty feet long, in which they are resolved; thence through a tube incased in a refrigerating envelope, T, which is kept constantly cool by a current of cold water; and are then condensed in the glass receiver, R. The operation is arrested as soon as one hundred or one hundred and fifty cubic centimetres of liquid—which will contain all the alcohol—have been condensed. The resultant liquid is again distilled in an
apparatus similar to the former one, but smaller. The latter operation is arrested when some five or six cubic centimetres of liquid have been condensed in a closed receiving-tube, which takes the place of the receiver R in the former apparatus. The tube is then taken away, and to its contents are added a little iodine and carbonate of soda; on heating it slightly, small crystals are precipitated of iodoform, a substance which could not be produced unless alcohol were present. M. Müntz has verified the results of this process by other test experiments. When distilled water, chemically pure, was heated in the same apparatus, the addition of iodine and carbonate of soda was not followed by any reaction. A second verification was obtained by distilling fifteen litres of pure water, to which one millionth part of alcohol had been added; the addition of iodine and carbonate of soda caused a precipitation of iodoform precisely like that which was obtained in treating tlie natural waters. One or two hundred grammes (three and a half to seven ounces) of tilled earth mixed with a pint of
water gave a similar precipitate of iodoform when distilled and exposed to the reactions employed in the other experiments. The precipitation
of iodoform by the addition of iodine and carbonate of soda is a very evident test of the presence of alcohol. Iodoform has marked characteristics which permit it to be distinguished very readily: the form of its crystals, particularly, is typical; it is of a light yellowish color, and appears under the microscope in the form of six-rayed stars derived from an hexagonal prism, of precisely the form of snow-crystals. The accompanying figures give photographic representations of the crystals as they appear under the microscope. Fig. 2 represents the crystals from pure water to which alcohol has been added in the proportion of one millionth; Fig. 3, those obtained from rain-water; Fig. 4, crystals from snow-water; and Fig. 5, those procured from cultivated soil. M. Müntz's first experiments were made about four years ago. He has since examined a
considerable number of samples of rain-and snow-water from Paris and the country. After each distillation the apparatus has been carefully cleansed by exposing it for some time to currents of vapor, and the analysis has been tested by repeating it in blank. More than eighty essays have given identical results. The quantity of alcohol contained in rain-, snow-, and sea-water may be estimated at from one to several millionths of the whole. Cold water and snow-water seem to contain a little larger proportion of it than warm water. Appreciable quantities of it are found in the water of the Seine; and the proportion is very sensibly increased in sewer-water. Vegetable mold appears to be rich in it; and it is probable that the natural alcohol originates in the soil from the fermentation of the organic matters contained in it, and is thence diffused as a vapor in the atmosphere. Meteoric waters absorb it at the moment of their condensation. These results are absolutely new, to our knowledge, and are the fruits of an entirely original labor.
- Translated from "La Nature."