290 FLUIDITY AND PLASTICITY TABLE LXXII.—THE FLUIDITIES OF VARIOUS VOLUME CONCENTRATION^ OF MALT FLOUK-WATEB MIXTURES AT 20°C (AFTER LUERS AND SCHNEIDER) 1 g flour displaces 0.6766 ml of toluene Volume, per cent Viscosity relative, observed Fluidity absolute, observed Fluidity absolute, calculated 0.000 1.000 100.5 100.5 0.338 1.010 99.5 98.6 0.676 1.042 96.5 96.6 1.352 1.090 92.2 92.8 2.704 1.192 84.3 85.1 5.408 1.433 70.1 69.7 8.120 1.844 54.5 54.2 10.816 2.566 39.2 38.9 13.520 3.459 29.0 23.5 16.240 4.839 20.8 8.0 There are certain cases where the fluidity-concentration relation is not linear as in case of Baker's data for nitrocellulose solutions. It seems unwise to make any sweeping deductions in regard to the meaning of these curves until they are confirmed by further observations, for it is possible that correction terms applied to the measurements might serve to rectify the curves. It is perhaps needless to add that if the curvature is real, it will have an important bearing upon the nature of colloids. I am engaged upon a study of this whole matter at the present time. In a few cases, of which one has been already cited, page 207, the fluidity curve consists of two linear branches, meeting at a sharp angle. This would seem to indicate a transition point, but in view of the uncertainties connected with the measurements of the viscosities of colloidal solutions, we may be pardoned for extreme caution in making such an assumption until the real existence of such a singular point has been thoroughly verified. Such a singular point is found for example in the data for aqueous solutions of sodium palmitate at 70°C as determined by Farrow (1912). The formula