ETHER. 



far impregnated, that its fragrance is in- 

 jured, and its odour rendered pungent 

 and acrid. A portion of water likewise 

 distils over, by which it is diluted. The 

 liquor in the retort, at the end of the 

 distillation, is also found diluted with 

 a portion of the water ; it is, however, 

 thick, and of a black colour, from a 

 quantity of carbonaceous matter sus- 

 pended in it. 



From the water and sulphurous acid 

 the ether is freed, by subjecting it to a 

 second distillation with a very gentle 

 hear appliecl_by a water-bath, pure pot- 

 ash being previously added to it, in the 

 proportion of two drachms to each pound ; 

 this attracts the sulphurous acid, and ren- 

 ders even the water rather less volatile. 

 Another method of rectification, propos- 

 ed by Peltetier, (" Memoires de Chimie," 

 torn. i. p. 316.) and revived by Dize, 

 ("Nicholson's Journal," 4to. vol. iii. p. 

 43,) which Mr. Murray, from whose 

 " System" the present article is extract- 

 ed, found to succeed extremely well, is, 

 to distil the ether of the first distillation 

 from a little black oxide of manganese, 

 the oxygen of which combines with the 

 sulphurous acid, converting it into sul- 

 phuric ; and this, with the water, re- 

 mains in the retort. Even after either of 

 these processes, the ether may still con- 

 tain a portion of alcohol, which usually 

 passes over in the first stage of the dis- 

 tillation. This is best abstracted by agi- 

 tation with water, which imbibes the 

 alcohol, and a little of the ether ; the 

 greater part of the ether floats above, 

 may be drawn off, and by distilling it 

 with a very gentle heat is obtained ex- 

 tremely pure. 



A degree of obscurity still prevails 

 with regard to the theory of the forma- 

 tion of sulphuric ether ; different views 

 having been entertained of the agency of 

 the acid on the alcohol. The explana- 

 tion that was generally given, after the 

 establishment of the theory of Lavoisier, 

 was founded on the supposition, that the 

 acid acts principal!} by communicating 

 oxygen. Alcohol consists of carbon and 

 hydrogen, with a portion of oxygen : 

 when mixed with sulphuric acid, and ex- 

 posed 10 heat, it was supposed that part 

 of 'he acid suffered decomposition, its 

 oxygen being attracted by the hydrogen 

 of the alcohol, and forming water ; the 

 balance of attractions between the prin- 

 ciples of the alcohol being thus broken, 

 part of its curbon is precipitated, and is 

 diffused through the liquor, rendering it 

 thick and dark coloured ; and the remain- 





ing quantities of its elements, its carbon, 

 hydrogen, and oxygen, unite and form 

 the ether. 



This explanation is founded on the sup- 

 position, that the sulphuric acid is 

 decomposed in the process by which 

 ether is formed. But a few years ago it 

 was affirmed by Fourcroy and Vauquelin, 

 from a series of experiments which they 

 undertook to elucidate this subject, that 

 such a decomposition of the acid is not 

 at all necessary to its formation : that al- 

 though it may take place to a certain ex- 

 tent towards the end of the process, 

 when the liquor is loaded with carbon, 1 

 there is no indication of it in the first 

 stage, during which, principally, the 

 ether is formed : no sulphurous acid gas 

 is discharged, and if the process be 

 stopped at the end of this stage, the re- 

 maining acid, they found, is capable of 

 saturating the same quantity of alkali as 

 before its mixture with the alcohol. 

 (" Nicholson's Journal," 4to. vol. i. p. 

 385.) 



These chemists gave, therefore, a dif- 

 ferent view of this subject, which they 

 applied even to the action of this acid 

 on vegetable matter in general. They 

 suppose that the sulphuric acid suffers 

 no decomposition, and that it acts no 

 other part than causing, by the exertion 

 of a disposing affinity, the decompos.tion 

 of the alcohol. By this affinity, it dis- 

 poses part of the hydrogen and of the 

 oxygen of the alcohol to combine and 

 form water : the balance of attractions 

 being thus subverted, a quantity of car- 

 bon is separated, and the remaining car- 

 bon, hydrogen, and oxygen, combine and 

 form ether. 



This theory, however, advanced by 

 these chemists, is not perhaps perfectly 

 established. Though they affirm, that 

 the acid remaining after the formation of 

 ether saturates as much alkali, as it 

 would do previous to its mixture with 

 the alcohol, the experiment by which 

 this is supposed to be established is not 

 altogether without fallacy. During the 

 formation of ether, there is always, also, 

 a formation from the elements of the al- 

 cohol, of some of the vegetable acids, 

 particularly of the acetous and oxalic. 

 The oxalic, it has been ascertained by 

 the observation of Cadet, is formed co- 

 piously even without heat, merely by 

 allowing the mixture of acid and alcohol 

 to remain at rest for some time. These 

 will contribute to the saturation of the 

 alkali ; so that if none of the sulphuric 

 acid were decomposed, more alkali ought 



