30J CONSIDERATION OF CARBON COMPOUNDS. 



Occurrence in nature. Many ethers are products of vegetable 

 life and occur in some essential oils; wax contains the com- 

 pound ether palmitate of melissyl, C 30 H 61 .C 16 H 31 O.O, and sperma- 

 ceti, a solid substance found in the head of the whale, is the 

 palmitate of cethyl, C 16 H 33 .C 16 H 31 O.O. The most important 

 group of compound ethers are the fats and fatty oils, which are 

 widely distributed in the vegetable, but even more so in the 

 animal kingdom. 



General properties. The ethers and compound ethers of the 

 lower members of the monatomic alcohols and fatty acids have 

 generally a characteristic and pleasant odor. Fruit essences 

 consist mainly of such compound ethers, and what is generally 

 known as the " bouquet " or " flavor " of wines and other 

 alcoholic liquors is chiefly due to ethers or compound ethers, 

 which are formed during (and after) the fermentation by the 

 action of the acids present on the alcohol or the alcohols 

 formed. The improvement which such alcoholic liquids undergo 

 " by age" is caused by a continued chemical action between the 

 substances named. 



All ethers are neutral substances ; those formed by the lower 

 alcohols and acids are generally volatile liquids, those of the 

 higher members are non-volatile solids. When compound 

 ethers are heated with alkalies, the acid combines with the 

 latter, whilst the alcohol is liberated. (The properties of the 

 compound ethers, termed fats, will be considered further on.) 



Ethyl ether, JEther (C 2 H 5 ) 2 == 74 (Ether, Sulphuric ether, Ethyl 

 oxide}. The name of the whole group of ethers is derived from 

 this (ethyl-) ether, in a similar manner as common (ethyl-) 

 alcohol has given its name to the group of alcohols. The name 

 sulphuric ether was given at a time when its true composition 

 was yet unknown, and for the reason that sulphuric acid was 

 used in its manufacture. 



Ether is manufactured by heating to about 140 a mixture of 

 about equal parts of alcohol and sulphuric acid in a retort, 

 which is so arranged that additional quantities of alcohol may 

 be allowed to flow into it, while the open end is connected with 

 a tube, leading through a suitable cooler in order to condense 

 the highly volatile product of the distillation. 



