366 TRANSACTIONS OF SECTION B. 



yet produce very small loaves. Dr. Hardy at the Winnipeg meeting of this 

 Association showed that gluten loses it's tenacity and ductility if it be deprived 

 of its electrolytes. Prof. T. B. Wood has demonstrated the profound influence 

 which very dilute solutions of acids, alkalis, and salts have on the physical 

 characteristics of gluten. It has been found that additions of very small per- 

 centages of salts natural to flour or wheaten ash do increase the size of the loaf 

 even though the production of gas in fermentation be unaffected or actually 

 diminished. 



The author came across a case in which the mere addition of water, if made 

 at a time substantially prior to dough making, increased the strength of the 

 flour to an extraordinary extent, even though the yield of gas in fermentation 

 was not appreciably increased thereby. 



He therefore, with the assistance of his colleague, Mr. A. G. Simpson, made 

 an investigation of the changes produced, the results of which were set forth in 

 detail. The most striking change in the flour itself appears to be the trans- 

 formation of organic phosphorus compounds into inorganic. As part of these 

 investigations, it has been found that during the process of baking a large pro- 

 (xjrtion of the organic phosphorus compounds becomes inorganic. 



British millers nowadays obtain their raw material from all parts of the 

 world, a multitude of varieties raised in environments ranging from arctic or 

 semi-arctic to tropical or semi-tropical. The climatic conditions in most districts 

 also vary greatly from season to season. From such extremely diverse and variable 

 materials, they have to produce flours of uniform qualities. It is therefore right 

 and proper that they should be allowed to make use of the advances in chemical 

 knowledge in the treatment of wheats and flours. Sometimes the desirable treat- 

 ment can be limited to the adjustment of water content, Nature herself being 

 thereby enabled to effect the necessary changes. 



Sometimes the addition of water fails to bring about these changes, or for 

 various reasons it is undesirable to raise the water content sufficiently, and in 

 such cases the addition of diastatic bodies, nitrogenous yeast-foods and salts 

 natural to wheat or wheaten ash is desirable and should be permitted. But 

 inasmuch as such permission might be abused, a Board of Reference consisting of 

 highly qualified physiologists, chemists, and business men should be established, 

 to whom all such processes and additions should be submitted, and to whom 

 millers and bakers should be responsible in such matters. 



TUESDAY, SEPT EM DEI? 5. 

 The following Papers and Reports were read : — 



1. Discussion on Colloids. 



(i) The Theory oj Colloids. By Professor H. Freundlich. 



The classical researches of Graham pointed to a fundamental difference 

 between crystalline and colloidal substances. The work of Zsigmondy with the 

 ultramicroscope proved colloidal solutions to be two-phase systems, containing 

 suspended particles. The quantitative experiments of Perrin and of Svedberg, 

 dealing with the Brownian movement, proved the colloidal solutions to form a 

 connecting link, without any sharp discontinuity, between coarse suspensions 

 on the one hand and true solutions on the other, although the differences 

 between the extreme terms of the series are very marked. Recent work on 

 true solutions, especially in respect to colour and solubility, indicates that the 

 simple theory of van't Hoff fails to take account of certain important 

 factors, notably of the combination of the dissolved substance with the solvent 

 which undoubtedly occurs in true solutions. On the other hand, coarse sus- 

 pensions are only formed by very sparingly soluble substances, which have 

 little tendency to react with the solvent. Colloidal solutions stand between 

 these two extremes. One class, distinguished from coarse suspensions only by 



