80 SIR WILLIAM RAMSAY 



led to interesting conclusions, and even at that time the results 

 with acetic acid proved to be of considerable interest, especially 

 as a comparison with the data obtained by Natanson with nitro- 

 gen peroxide was possible. These two substances, acetic acid and 

 nitrogen peroxide, .were found to behave so similarly as regards 

 their vapour densities and, as our own results showed, as regards 

 their vapour pressures and boiling points, that we felt entitled 

 to conclude that the kind of dissociation they undergo must be 

 very similar. 



The liquids investigated were methyl, ethyl and propyl alcohol, 

 ether, acetic acid and water. The experimental work was carried 

 out conjointly in Bristol in the case of methyl and ethyl alcohol, 

 ether and acetic acid. The work on propyl alcohol had just 

 been started when Ramsay was appointed Professor of Chemistry 

 at University College, London, and I did the greater part of this 

 work afterwards by myself in Bristol. I also carried out a 

 number of experiments on the mixture of propyl alcohol and 

 water of constant boiling point. The experiments with water 

 were carried out by Ramsay in London, with the exception of 

 those on the vapour densities under low pressures with the 

 modified Hofmann's apparatus, which I made in Bristol. 



I may mention in passing that the experiments with propyl 

 alcohol and water led us to the conclusion that the so-called 

 " hydrate of propyl alcohol," described by Chancel, has no 

 existence, and we read a paper on the subject before the Chemical 

 Society in London. Our conclusions, however, were received 

 with scepticism, and the paper was not published in the Trans- 

 actions (Proc. Chem. Soc. 1888). Nine years later Thorpe (Trans. 

 Chem. Soc. 71, 920) brought forward evidence against the existence 

 of any of the four ' hydrates of isopropyl alcohol,' described by 

 different observers. Finally, in 1902, a careful study of mixtures 

 of the lower alcohols with water was carried out by Miss E. 0. 

 Fortey and myself, and our results, taken in conjunction with 

 those of Konowalow, afford strong evidence that no hydrate of 



