Gelatine
2 of the 7 encyclopedias on this shelf carry an entry for Gelatine. Both are reproduced below, so you can see where they agree and where they differ.
Collier's New Encyclopedia (1921)
or GELATIN (Latin, gelatus frozen, so named from the tendency which the substance has to congeal and become to a certain extent solid), in chemistry, C76H124N24O29.? Animal mal glutin, obtained by treating bones with dilute hydrochloric acid, which dissolves the mineral constituents of the bone, consisting of phosphates and carbonates of calcium, magnesium, etc., and leaves the bone cartilage. This, when boiled for a long time with water, dissolves, and forms gelatine, which can be purified by dissolving in hot water and precipitating by alcohol. A pure variety is obtained from the swimming bladder of the sturgeon, or other species of Acipenser. Impure gelatine, called glue, is prepared by boiling down pieces of hide, horn, hoof, cartilage, etc., with water under pressure. Pure gelatine is amorphous, transparent in thin plates, of a yellowishwhite color; it has neither taste nor smell, and is neutral to vegetable colors; it is insoluble in alcohol and in ether. In contact with cold water it swells up, and is soluble in hot water. Gelatine subjected to dry distillation yields methylamine, cyanide of ammonium, pyrrol, etc.; by oxidation with sulphuric acid and manganese dioxide, or with chromic acid mixture, it yields hydrocyanic acid, acids of the fatty series, benzoic aldehyde and benzoic acid, etc. Gelatine boiled with caustic potash yields glycocine and leucine. Gelatine contains about 50 per cent. of carbon, 6.6 of hydrogen, and 18.4 of nitrogen; when pure it probably contains no sulphur.
Aiton's Encyclopedia (1910)
jel'a-tin, a substance obtained by dissolving the gelatinous portions of animals. Gelatine of animals corresponds to the juices of fruit and plants. It is obtained chiefly from horns, hoofs, tendons, cartilage, bones, and portions of hides. In a particularly pure form, derived from the air bladders of certain fishes, especially the sturgeon, it is called isinglass. In a crude form, gelatine is the glue of commerce. Pure gelatine capsules are used by druggists to contain doses of disagreeable medicine. Gelatine plates serve a useful purpose in photography. Gelatine in its various forms is now one of the important by-products of packing houses. See Isinglass ; Glue