250 



SCIENCE 



[N. S. Vol. XLIV. No. 1129 



Report of a Survey of the Food Conditions at 



Sing Sing Prison: Emily B. Seaman. 

 The Relation of Biological Chemistry to Problems 



of the Community : Emily B. Seaman. 

 Washing and Cleaning : W. D. Bancroft. 

 Whipped Cream, Etc.: W. D. Bancroft. 

 Mayonnaise: "W. D. Bancroft. 

 On Soap Jelly Formation : G. H. A. Clowes. 



NaCl or other Na salts added to slightly alka- 

 line soap solutions cause jelly formation between 

 .2N and .iN, and precipitate at higher concentra- 

 tions. 



Same salts added to neutral or slightly acid soap 

 cause opalescence at .2N, gradually increasing until 

 complete precipitation occurs above .4V. 



Degree of dispersion of negative soap particles 

 depends on adsorbed anions derived from added 

 alkali. Subsequently adsorbed cations cause ag- 

 gregation. Larger particles with smaller charge 

 precipitate earlier, smaller particles with larger 

 charge coalesce later forming jelly. If at critical 

 cation concentration particles still exhibit active 

 Brownian movement, jelly is subsequently formed 

 enclosing water in interspaces, otherwise precipi- 

 tation occurs. 

 On Filtration of Blood Plasma: G. H. A. Clowes 



and F. West. 



In 1913, writers confirmed Cramer's observation 

 that citrated plasmas may be obtained by filtra- 

 tion through Berkefield bougies which coagulate 

 with thrombin but not with calcium alone. Bougie 

 removes lipoids. Addition of sterilized brain 

 lipoid one part in 50,000 causes coagulation with 

 calcium. Added lipoid may be entirely removed 

 by second filtration prior to addition of calcium. 

 Besulting filtrate does not clot with calcium. 



Cleaned and sterilized bougies often contain 

 sufficient calcium to cause local coagulation of 

 plasma with consequent production of thrombin 

 which passes into the nitrate, complicating subse- 

 quent experiments. This may afford explanation 

 of Goddard's results. 

 Mechanism of Blood Coagulation: G. H. A. 



Clowes. 



Dispersion of negatively charged fibrinogen and 

 lipoid particles is normally maintained by ad- 

 sorbed anions. Analogous, antagonistic, electro- 

 lyte effects in emulsions, jellies and blood coagu- 

 lation suggest probability that Ca by adsorption 

 first lowers charge and promotes deposition of 

 lipoid film on fibrinogen particles, and subse- 

 quently Ca soaps, being freely dispersed in lipoids 

 involved, cause surface tension changes and trans- 

 position of phase relations analogous to those ob- 



served in emulsions, the previously dispersed fibrin- 

 ogen becoming the continuous fibrin clot in which 

 water is more or less dispersed. Presumably 

 thrombin, by local adsorption, promotes hydrol- 

 ysis, liberates acid groups, lowers negative charge, 

 raises surface tension, and so promotes aggrega- 

 tion. 



Investigation of the Kjeldahl Method for Deter- 

 mining Nitrogen. A New Aeration Apparatus: 

 I. K. Phelps and H. "W. Daudt. 

 Polin's method for determining ammonia is 

 adapted to the Kjeldahl method. All of the opera- 

 tions, including the measurement and addition of 

 the sodium hydroxide solution, the passing of air 

 through the resulting alkaline solution and the ab- 

 sorption of the ammonia in standard acid are car- 

 ried on by means of air pressure or suction. The 

 advantages over the more commonly used distilla- 

 tion method are discussed. 



Remarks on the Physical and Biological Chemistry 

 of Fat: Martin H. Eischer. 

 The general principles governing the production 

 and the destruction of water-in-oii and oil-in-water 

 emulsions and their general properties are dis- 

 cussed. Protoplasm represents ordinarily a fine 

 oil-in-water emulsion. The characteristic feature 

 of "fatty degeneration" is a coalescence of these 

 fine droplets into coarser ones, the conditions pro- 

 ducing such being identical with those producing 

 the coarsening of an oil-in-water emulsion. Adi- 

 pose tissue, butter formation and the formation of 

 fatty secretions consists in the conversion of the 

 oil-in-water type of emulsion into the water-in-oil 

 type. The experimental facts underlying these 

 conclusions are illustrated. 



Studies Upon the Effects of Acids: Arthur D. 

 Bjrschfelder. 



Repetition of the experiments of Hofmeister 

 and Martin Eischer on the swelling of fibrin in 

 m ixtures of acids and neutral salts, show that the 

 solutions in which swelling seems to be inhibited 

 (except the sulphates) are much poorer in hydro- 

 gen ions than the corresponding ones in which this 

 is only slightly the case; and that when these are 

 all brought to the same hydrogen ion concentration 

 the amount of swelling is the same in all the so- 

 lutions except those containing sulphates which 

 markedly inhibit. Varying either the chlorine ions 

 or the other ions to bring about the acidification 

 gives the same results. Adding a little dilute 

 H 2 S0 4 or Na^SOj to mixtures already swollen 

 under the influence of other acids causes marked 

 shrinking. 



However, injection of phenolsulphonphthalein, 



