

LIGNINE, OR WOODY FIBRE. 107 



value in some forms of dispepsia, as it sometimes passes the system 

 undigested. As animal food requires less modification in the process 

 of assimilation than vegetable food, the animal aliments, and especially 

 jellies, have been used in preference to farinaceous substances in this 

 and other cases where the latter have been recommended. 



Of tb.3 amylaceous matter of arrow-root, salep, tapiaco, sago, &c. 

 we have elsewhere spoken. The quantity of starch in rice has been 

 turned to account in England by a patent for obtaining it, which is 

 simply by the addition of a weak solution of caustic alkali; and in 

 another patent an alkaline salt is substituted. The still larger pro- 

 portion of starch afforded by Indian corn is also said to have led to 

 the establishment of manufactories of starch from it in this country. 

 No substance, it has been said by a distinguished physician, is so 

 much relished by infants when weaned, or which is less apt to turn 

 sour, as the tapiaco starch. The milk and other preparations of this >- 

 and other kinds of starch are made like that of sago ; but less boiling ? 

 is required. 



Lignine, or Woody Fibre, as an Alimentary Principle. This is the 

 substance of all vegetable tissues, and is obtained by submitting vege- 

 tables successively to the action of ether, alcohol, water, diluted acids 

 and alkalies, in all of which it is insoluble. The proportion of 

 lignine in 100 parts of rice is 4.8, Barley; (husk) 18.75, Oats (bran) 

 34, Rye (husk) 24, Peas 21, Garden bean 25, Kidney do. 18, Potato 

 4 to 10, &c. The proportions of this and of other principles in the 

 fruits will be given in another volume. Amylaceous fibre, often spo- 

 ken of by writers, is not essentially different from the woody fibre ; 

 and its composition is probably nearly the same. In most plants it is 

 composed of nearly equal parts of carbon and water. 



It is doubtful as to lignine being a nutritive principle with man, 

 though it is the common food of many insects and some other animals. 

 It requires to be reduced and otherwise preprared, when it resembles 

 the amylaceous powders. Under bread we have spoken of it as af- 

 fording that article to the Laplanders, but as starch is diffused through 

 the plant by the sap, this may form the nutritive principle attributed 

 to lignine. 



It is certain that the ligneous matter of most of our common vege- 

 table food is quite indigestible, and is consequently evacuated. Thus 

 the skin of potatoes, grapes, the peal and cores of apples, and other 

 fruits, and the shells and stones of nuts, plums, cherries, the coats of 

 the grains, seeds of peas, beans, melons, &c., are all incapable of assi- 

 milation, and ought always to be removed, as they are very liable to 

 cause obstructions in the alimentary canal. 



We do not doubt that many, very many, deaths are occasioned by 

 eating thick and tough-skinned fruits without removing these indiges- 

 tible and refractory substances before the fruit is eaten ; for they very 



