Mr. Müntz's method of procedure is as follows: He submits to distillation three or four gallons of snow, rain, or sea water in an apparatus such as shown in Fig. 1. The part which serves as a boiler, and which holds the liquid to be distilled, is a milk-can, B. The vapors given off through the action of the heat circulate through a leaden tube some thirty-three feet in length, and then traverse a tube inclosed within a refrigerating cylinder, T, which is kept constantly cold by a current of water. They are finally condensed in a glass flask, R, which forms the receiver. When 100 or 150 cubic centimeters of condensed liquid (which contains all the alcohol) are collected in the receiver, the operations are suspended. The liquid thus obtained is distilled anew in a second apparatus, which is analogous to the preceding but much smaller (Fig. 2). The liquid is heated in the flask, B, and its vapor, after traversing a glass worm, is condensed in the tube, T. The operation is suspended as soon as five or six cubic centimeters of the condensed liquid have been collected in the test-tube, R. The latter is now removed, and to its liquid contents, there is added a small quantity of iodine and carbonate of soda. The mixture is slightly heated, and soon there are seen forming, through precipitation, small crystals of iodoform. Under such circumstances, iodoform could only have been formed through the presence of an alcohol in the liquid. These analytical operations are verified by Mr. Müntz as follows: He distills in the same apparatus three to four gallons of chemically pure distilled water, and ascertains positively that under these conditions iodine and carbonate of soda give absolutely no reaction. Finally, to complete the demonstration and to ascertain the approximate quantity of alcohol contained in natural waters, he undertakes the double fractional distillation of a certain quantity of pure water to which he has previously added a one-millionth part of alcohol. Under these circumstances the iodine and carbonate of soda give a precipitate of iodoform exactly similar to that obtained by treating natural waters. [Illustration: Fig. 3.--IODOFORM CRYSTALS OBTAINED DIRECTLY (greatly magnified).] [Illustration: FIG. 4,--IODOFORM CRYSTALS OBTAINED WITH RAIN WATER.] In the case of arable soil, Mr. Müntz stirs up a weighed quantity of the material to be analyzed in a certain proportion of water, distills it in the smaller of the two apparatus, and detects the alcohol by means of the same operation as before. [Illustration: FIG. 5.--IODOFORM CRYSTALS OBTAINED WITH SNOW WATER.]