Experimental researches on the food of animals, and the fattening of cattle. With remarks on the food of man / By Robert Dundas Thomson.

  • Thomson, Robert Dundas, 1810-1864.
Date:
1846
Catalogue details

Licence: Public Domain Mark

Credit: Experimental researches on the food of animals, and the fattening of cattle. With remarks on the food of man / By Robert Dundas Thomson. Source: Wellcome Collection.

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    in minute quantities, which corresponded with the properties of acetic acid; but it is the only acid which distils over from the liquor of the stomach at a temperature of 212°. The filtered liquid of the stomach, under such circumstances, contains no hydrochloric acid, but an acid which is either lactic, or corresponds very closely with it.* To ascertain if free hydrochloric acid was present in the fluid contents of the stomach, after being distilled for some hours till no more acetic acid came over, the residue was filtered, and divided into three equal portions. 1. To the first portion a solution of nitrate of silver was added, until a precipitate ceased to fall; pure nitric acid was then added, and the temperature raised to the boiling point. The precipitate was filtered, washed, and weighed. 2. The second portion was evaporated to dryness, and ignited: the residue was dissolved in water, and precipitated by nitrate of silver, nitric acid bemg added, and the so- lution boiled. 3. The third portion was ex- actly neutralised with caustic potash, evaporated, and ignited, the residue was dissolved in water, and precipitated by nitrate of silver. The results of these experiments are indicated in the following table in grains: — * Phil. Mag., April, May, 1845. Lancet and Medical Gazette of same year.