430 M. Vauquelin's Analysis of the [June, 



the same state, although in different proportions, both with 

 respect to the whole mass and to the oil. 5. Almond whey 

 may, in many cases, form a mild and pleasant beverage to inva- 

 lids, where the emulsion could not be digested, in consequence 

 of the quantity of albumen which it contains. 6. Starch, or 

 amylaceous fecula, does not form the base of the emulsive seeds, 

 as was formerly supposed to be the case. 



Article VI. 



Analysis of the different Varieties of Potatoes. By M. Vau- 



quelin.* 



The Society of Agriculture commissioned M. Vauquelin to 

 undertake the analysis for the purpose of ascertaining the relative 

 proportions of starch, parenchyma, and extract, which each 

 species contained. The whole number of varieties which he 

 examined was 47 : of these, 1 1 varieties furnished from }to| 

 of their weight of starch ; two only yielded no more than ±. 

 The 11 varieties, which gave the most starch, lost only $ of 

 their weight in drying ; 10 lost •§- , and six nearly ■§■ by this pro- 

 cess. The author observes that the actual quantity of starch is 

 greater than what may appear from his table, as a considerable 

 quantity still remains attached to the parenchyma : so that he 

 concludes that the poorest or least nutritive potatoe contains at 

 least -i- of its weight of starch, and the richest about 28 parts in 

 the 100. The starch was separated from the parenchyma by 

 employing a large quantity of boiling water ; but it appears that 

 in this way a portion of gummy matter would also be carried off, 

 which is contained in the potatoe ; that this is the case is proved 

 by this circumstance, that mucic acid is formed by the action of 

 nitric acid upon potatoe starch. The proportion of proper 

 parenchyma appears to be very small, generally about 0T5, and 

 often not more than -01. When totally deprived of its starch 

 and gum, the parenchyma appears to resemble mere woody 

 matter. 



The author examined the water in which the pulp of the 

 potatoe had been washed ; it was evaporated, and was found to 

 contain a substance that was coagulable by heat, together with 

 some that remained miscible with the water. The coagulabl 

 matter was separated, and from its sensible and physical proper- 

 ties seemed to be albumen. The soluble matter was then ob- 

 tained by evaporation ; it consisted of two substances, one 

 soluble in alcohol, which appeared to be of a resinous nature, 



» Abridged from Journ. Pity?. August, IS1". 



