ALCOHOL FROM CELLULOSE. 177 



varieties being sometimes sold under the name of honey. A great 

 deal of the starch sugar made is directly fermented and distilled 

 in order to prepare spirits of wine for manufacturing purposes and 

 as a beverage ; some kinds of rectified spirit thus produced are 

 eminently unwholesome, on account of the presence of injurious 

 impurities, more especially fusel oil (Expt. 85). In converting 

 starch on a manufacturing scale the materials are usually not 

 boiled in open pans, but heated together in pressure boilers, which 

 facilitates the action. 



Expt. 192. Alcohol from Cotton and Linen or Paper. The 

 woody matter of most vegetables mainly consists of a substance 

 called cellulose, which is obtained in different conditions from 

 different plants ; thus the fibres of hemp and flax stalks, the down 

 or filaments of the cotton seed, and the analogous products derived 

 from jute, Esparto grass, and numerous other sources of vegetable 

 textile fabrics and paper pulp, all consist essentially of cellulose in 

 some form or other. Chemically, cellulose is closely related to 

 starch and sugar, being formed from and transformed into bodies 

 . of these natures during the growth and life of plants and trees, 

 and being also capable of transformation into sugar by chemical 

 means. Thus the action of certain mineral acids, more especially 

 sulphuric acid, will convert cotton and linen into sugar, which is 

 one reason why splashes of acid are apt to rot and burn holes in 

 clothing (Expt. 139). 



Cut up a piece of calico or linen (part of a shirt will do) into 

 small shreds, and stuff them into a large flask; pour on some 

 sulphuric acid, and shake it about so as to moisten the shreds 

 thoroughly with the acid ; allow the whole to stand an hour or 

 two, then add some water (about half a pint to every ounce of 

 acid used), and boil gently for some hours, adding a little water 

 from time to time to replace that lost by evaporation. Pour the 

 whole out into a basin, and gradually add powdered chalk little by 

 little with continual stirring; copious effervescence will ensue, 

 owing to the production of sulphate of calcium and carbon dioxide, 

 as in the last experiment ; when all the acid is neutralised, strain 

 off the clear liquor (adding a little more water if necessary), and 

 press the sulphate of calcium mud in a calico filter or bag, so as to 

 squeeze out as much fluid as possible. Filter this liquid clear 

 through paper, and evaporate the solution on the water bath. 

 Finally a tolerably clear solid sugar will be obtained, which may 

 be used to sweeten a cup of tea, or fermented with yeast, as in 

 Expt. 189. 



Paper and even sawdust can be similarly treated with much 

 the same result, excepting that the more compact nature of the 



M 



