SUBSTITUTION PRODUCTS OF THE HYDROCARBONS 39 



stances generally used are fruit, most vegetables, especially 

 potatoes, inferior grain, sawdust, etc. The utilization of 

 cellulose, the carbohydrate constituent of sawdust and other 

 woody material, for the production of alcohol has been recently 

 developed and several processes have been patented. The 

 general principle of all of them is to first hydrolyze the cellulose 

 to glucose sugar, usually by acid hydrolysis, and then to fer- 

 ment the glucose to alcohol by means of yeast, as already de- 

 scribed. 



The Higher Alcohols 



Amyl Alcohols. — The only alcohols, in addition to the two 

 already described, which we shall consider are the amyl alcohols 

 which contain five carbon atoms, i.e. C5H11OH. There are 

 eight different isomeric amyl alcohols, all of which are fully 

 explained by our ideas of structure which will not be discussed 

 here but will be taken up again under lactic acid, p. 69. Two 

 of these are found in the products of distillation when a fer- 

 mented liquor is distilled. They are known together as fer- 

 mentation amyl alcohol. These two alcohols with propyl alcohol 

 and butyl alcohol, the two preceding members, constitute the 

 greater part of what is commonly known as fusel oil and on ac- 

 count of which the oil is also called crude amyl alcohol. 



Amyl alcohol as it is ordinarily obtained, which is a mixture 

 of at least tv/o of the eight isomers, is a heavy hquid boiling at 

 about 130°, sp. gr. about 0.81. It shows a marked difference 

 from methyl, ethyl and propyl alcohols in not being soluble in 

 water. It is a striking fact that the solubility in water de- 

 creases as the amount of carbon in the alcohol increases, and 

 at the same time the specific gravity increases and the boiling 

 point rises. The lower alcohols are thus water-like volatile 

 liquids soluble in water. The intermediate members from 5 

 to 10 carbon atoms are heavy liquids, difficultly volatile and 

 insoluble in water, while the higher members are solid, wax- 

 like compounds, non-volatile and insoluble in water. 



