37^ IIEINRICII ROSE ON ^TIIERIFICATION. 



water. The fifth was the first that contained free water, and 

 indeed, in vokxme, more than the half. The specific gravity of 

 the ajthereal Uquid floating above it was not determined. This 

 last product distilled over very slowly, although at times the 

 temperature was raised to 100° R. 



It results from these experiments that aether which is pro- 

 duced at lower temperatures than is requisite to boil the mix- 

 ture, is at the same time purer, and contains less alcohol and 

 water than sether which has been prepared by strong boiling. 

 A comparison of the specific gravities with those previously 

 mentioned, set this evidently beyond all doubt. At a low 

 temperature the water especially escapes later, and therefore 

 only in the last product could separated water be observed, a 

 proof that it is not disengaged in company with the aether. 



II. A second series of experiments proved this in a still more 

 decided manner, so that there can no longer remain any doubt 

 on the subject that aether can be evolved in abundant quantity 

 at the boiling-point of water. 



Seventeen ounces of anhydrous alcohol of specific gravity 

 0*792 were mixed cold with 18 ounces of the hydi'ate of sul- 

 phuric acid, and the mixture subjected to distillation in a water- 

 bath whose temperature frequently did not even attain that of 

 boiling water. The quantities taken are in the proportion of 

 single equivalents of each of the substances employed ; they 

 were taken in this proportion, partly because it approaches 

 that which otherwise is employed in the preparation of aether, 

 when equal parts by weight of alcohol and sulphuric acid are 

 employed, and also in order to have no excess of sulphuric 

 acid. 



The results of the experiments are as follow : 

 First product : 3 drs. 



Second product : 3 oz. 6 drs. ; spec. gr. 0*755. 

 Third product : 3 drs.; spec. gr. 0-745. 

 Fourth product. 



Even the first product consisted of nearly pure jether ; for a 

 solution of acetate of potash separated aether from the liquid to 

 the amount of two thirds of its volume. 



The fourth and last products contained fi-ee water, and con- 

 sisted of nearly half of it by volume ; but it distilled over so 

 slowly in the water-bath, that several hours were necessary to 

 obtain a few urachms of it. From the specific gravities it will 



