570 TRANSACTIONS OP SECTION B. 



solution had not been generally re-cognised. Indeed, such association is hardly 

 to be expected on account of the high dielectric constant of water. 



The authors have found molecular association in water to be quite extensive 

 among aromatic substances. Benzoic acid, for example, is associated in water 

 even to a greater extent than in benzene. 



The view suggested by Meldrum and Turner, that the association in water may 

 be accounted for by supposing the molecular complexes to undergo dissociation, 

 is borne out by the results now obtained in water and by others in ethyl alcohol 

 as solvent, in which normal substances, such as benzyl and diphenylamine, are 

 apparently associated. 



5. The Problem of Molecular Association : I. The Affinities of the 

 Halogen Elements. By W. E. S. Turner. 



The author undertook a criticism of Abegg's and other recent theories of 

 valency, in so far as these theories attempt to account for molecular association 

 and for the existence of and formation of molecular compounds. The paper 

 embodied the results of the determination, in solution, of the molecular weights 

 of fifty to sixty halogen-containing substances of different types, the examination 

 of mixtures of such halogen compounds, and of iodine and these compounds, and 

 included a review of the molecular weights of all types of halogen-containing 

 bodies. 



It was shown that molecular association occurs only when the halogen com- 

 pound is an electrolyte, that there is no special virtue in the halogen elements — ■ 

 such as the existence of a large number of contra or residual valencies — neither 

 is there any virtue in the halogen ion differentiating it from other ions. Thus it 

 was shown that, in neutral solvents, nitrates are strongly associated. 



Throughout it was demonstrated that molecular association in neutral solvents 

 is the reciprocal of the supposed electrolytic dissociation in the dissociating 

 solvents. The question of the origin of the electrical forces which appear on 

 1 ionisation ' was also raised. 



Formation of molecular compounds was shown, except possibly in the case 

 of the periodides, not to be due to the same forces which bring about molecular 

 association in an individual substance. 



Lastly, the parallel which exists between the extent of association and the 

 conducting power in a solvent was shown to be a close one in the case of the 

 halogen-containing substances. 



6. Formation of Tolane Derivatives from Benzotrichlorides. 

 By Dr. J. Kenner and E. Witham. 



7. The Nitro Chloro and the Dichlorotoluene Sulplionic Acids. 

 By Dr. J. Kenner and Professor W. P. Wynne, F.R.S. 



8. The Action of Metals upon Alcohols. By Dr. F. M. Perkin. 



9. Report on Dynamic Isomerism. — See Reports, p. 80. 



10. Report on Aromatic Nitroamines. — See Reports, p. 82. 



11. Report on the Study of Isomorphous Sulphonic Derivatives of 

 Benzene. — See Reports, p. 100. 



12. Report on the Study of Hydroaromatic Substances. — See Reports, p. 82. 



