CONIINE. This alkaloid, first isolated by Giesecke in 1827, occurs in hemlock (q.v.) along with several closely related alkaloids (see ALKALOIDS) and can be prepared in a crude state by the process described for nicotine (q.v.); these alkaloids are all highly toxic. Coniine, C8I-1„N, is a colourless, strongly alkaline liquid, which boils at 166-167° C, and solidifies at —2° C to a crystalline mass. Its specific rotation is [ab —15.7°, it dissolves water, but is itself sparingly soluble in that solvent though readily soluble in ether or alcohol. The salts crystallize well; the picrate, which melts at 75° C, and the double compound with potassium cadmium iodide, which melts at 118° C, are characteristic and suitable for identification of the alkaloid. Coniine is one of the simplest of the natural alkaloids and was the first to be synthe sized (Ladenburg, 1886).