The Rotary Properties of Some Vegetable Proteids

So t~r as the writer has been able to ascertain, no reliable determinations have ever been made of the rotary properties of any of the vegetable proteids, although some of them can now be obtained in a pure state and in considerable quantities. The object of this investigation was to determine accurately the rotary power of some of the crystallized vegetable proteids. The globulin found in hemp seed was chosen as the main subject of study, because it could be obtained in a perfect]), crystalline form with comparative ease. For purposes of comparison, the rotar S powers of the crystallized globulins obtained from flaxseed and the Brazil nut were also determined under similar conditions. The identity of each of these three proteids has been completely established by the researches of Osborne; a Chittenden and Mendel,t and others, and a guarantee of chemical purity is furnished in their crystalline tbrm. Their individual compositions and properties will be described later in connection with the results of the polarimeter observations. A complete determination of the rotary properties of any substance should include a study of the effect on its rotary power of three factors--(1) the solvent used ; (2) the concentration of the solution ; (3) its temperature. The proteids investigated by the writer were imperfectly soluble in most solvents at the temperature of the room, and their solutions were more or less coloured. On account of their opacity, only dilute solutions containing abont one or two