of Sulphuric Acid and AlcoJwL 347 



mixture of sulphuric acid and alcohol by heat, is proved by 

 the following experiment. Five hundred grains of oil of vitriol 

 were diluted by five hundred grains of water; when cold, to 

 the dilute acid was added two thousand grains of alcohol, spe- 

 cific gravity 0'820. The following day this mixture was ex- 

 amined for sulphovinic acid, but none had been formed : it 

 was placed in a retort, and a quantity distilled off" nearly equal 

 to the weight of the alcohol employed : this had a specific gra- 

 vity of 0-84-2. Carbonate of potash separated a considerable 

 portion of water, the original alcohol would not even moisten 

 that salt: the residue in the retort was examined, and now 

 sulphovinic acid was found ; the evidence of which was, car- 

 bonate of lead being dissolved in considerable quantity; here 

 sulphovinic acid had been formed by heat, where it did not 

 previously exist. This result appears also opposed to the opi- 

 nion, that in the formation of a!ther the sulphuric acid acts 

 simply by abstracting water from the alcohol ; for the dilute 

 acid here gave up a portion of its water during the distillation, 

 and separated from the alcohol a portion of hydrocarbon. 



It has already been shown (9.) that the production of aether 

 is materially influenced by the quantity of water present, and 

 that the same sulphovinic acid will yield either aether or al- 

 cohol, as it is in a concentrated or dilute state. The hydro- 

 carbon which, as was shown in the former paper, has the ex- 

 traordinary power in oil of wine of neutralizing the whole of 

 the acid properties of sulphuric acid, and in sulphovinic acid 

 of neutralizing the half of them, being in the latter body in 

 so peculiar a condition that it will unite either with that pro- 

 portion of water necessary to form aether, or with the larger 

 proportion requisite to form alcohol, according to circum- 

 stances. 



In the experiments (8. 9.), in the production by distillation 

 of aether or alcohol from sulphovinic acid more or less diluted, 

 it appeared that sulphovinic acid might easily have its proxi- 

 mate elements separated and restored to their original state of 

 sulphuric acid and alcohol. The following experiment was 

 made with a view to illustrate this point. Five hundred grains 

 of acid and five hundred grains of alcohol were mixed as be- 

 fore, and left for several days : by previous experiment it is 

 known that more than half the sulphuric acid in this way be- 

 comes sulphovinic acid (4). By distillation and dilution at 

 })roper jieriods this would have given aether and alcohol, and 

 nearly the whole of the sulphuric acid (7.)- but instead of 

 doing tills, it was mixed witli one thousand grains of water, 

 and then distilh^d initil 1100 grains had |)assed over. No 

 charring or decomposition of the sulphuric acid look place ; no 

 2 V 2 ifcther 



