HOW MOLECULES MAKE MASSES 61 



so cells of like species tend to segregate, as has so ably been dem- 

 onstrated by Professor Herbert S. Jennings. 43 When a hetero- 

 geneous mixture of bacteria is agglutinated by a heterogeneous 

 mixture of specific antisera, each cluster of bacteria is homo- 

 geneous. Apparently each bacterium selectively adsorbs a layer 

 of its own specific antibody, and the bacteria so conditioned 

 cohere or "crystallize" into lattices or clumps because of the specific 

 unions of their new surfaces. The adsorbed antibody appears to 

 act like a cohesive colloid. 44, 45 



REFERENCES 



1 Zechmeister's paper entitled Cis-Trans Isomerization and Stereochemistry of 

 Carotenoids and Diphenylpolyenes, Chemical Reviews (1944), 34, 267-334. 



2 "Colloid Chemistry," Vol. VI, p. 748, New York, Reinhold Pub. Corp., 1946. 



3 Liher XXXV, Par. 185: Virus alarum sudoresque sedat. 



4 See, e.g., "Molecular Association," by W. E. S. Turner, in "Colloid Chemistry," 

 Vol. I, pp. 278-287, New York, Reinhold, 1926. 



5 "Properties of Ordinary Water-substance in All Its Phases," A. C. S. Monograph, 

 Reinhold Publishing Corp., 1940. 



6 /. Chem. Physics, 1933. 



7 /. Phys. Chem., 1936. 



& Phil. Trans. Roy. Soc, 1861, 151, 184. 



9 His original papers were printed in the Journal of the Russian Chemical Society, 

 1906-1908, and a comprehensive paper by him appeared in "Colloid Chemistry, 

 Theoretical and Applied," Vol. I, pp. 27-101, New York, Reinhold, 1926. 



10 See J. Alexander, First Colloid Symposium Monograph, 1923, p. 297, and also 

 paper of H. A. Endres, "The Crystallization of Sulfur in Rubber," in Colloid Chem- 

 istry, Vol. I, pp. 808-13, Reinhold Publishing Corp., 1926. Both papers have several 

 illustrations of these phenomena. By ultramicroscopic examination, J. Alexander 

 found that the sulfur-Canada balsam crystals showed ultramicrons at their surface, 

 apparently representing pai tides unable to find placement in the crystal lattice. 

 Vogelsang expressed the view, also shared by G. Quincke, that globulites are 

 preliminary stages in the formation of crystals. Sir J. S. Flett more recently drew 

 attention to these forms. 



11 Trans. Faraday Soc, 1933, 29, 990. 



12 For further information in this interesting field, see a paper by G. Friedel on 

 "The Mesomorphic States of Matter," in "Colloid Chemistry," J. Alexander, Vol. I, 

 pp. 102-125 (Reinhold Publishing Corp.), which gives references to other work. 



13 Robert Boyle, "Origin of Forms and Qualities," Oxford, 1666, and Rome de 

 l'lsle, "Crystallographie," I, p. 379, Paris, 1783. 



14 See the papers of Stephane Leduc (Nantes) and of A. L. Herrera (Mexico) in 

 "Colloid Chemistry," Vol. II, pp. 59-79, and pp. 81-91, Reinhold Publishing Corp., 

 1928. 



15 Science, 1925,61, 184. 



16 "On the Influence of Colloids upon Crystalline Form and Cohesion, with Ob- 

 servations on the Structure and Mode of Formation of Urinary and other Calculi," 

 London, 1879. 



17 Ord, Chapter II, "Containing a Discussion of the Causes of Molecular Coales- 



