M. Bechamp on Nitric Compounds of Starch. 527 



mixture filtered. To the filtrate a small quantity of water is 

 added, which separates a viscous mass ; this, treated with a large 

 quantity of water, is resolved into a white powder, which when 

 dried is quite homogeneous. 



The mass thus obtained is insoluble in alcohol or ether, or in 

 a mixture of the two. 



If in the above process a larger quantity of nitric acid be used, 

 and the temperature be not allowed to sink too rapidly, a per- 

 fectly transparent solution is obtained, which thrown into water 

 gives a less caseous and more pulverulent precipitate. This, 

 washed and dried, constitutes a new compound ; for, unlike the 

 other, it is soluble in a mixture of alcohol and ether. 



Both these substances have the composition C 12 H 9 NO 14 , or 

 C 12 H 9 O 9 NO 5 : Bechamp names the former mononitric starch, 

 and the latter isomononitric starch. 



A dinitric compound is obtained by dissolving starch in 12 

 parts of nitric acid, and then pouring into it 8 parts of concen- 

 trated sulphuric acid. The whole mass is then poured into a 

 large quantity of water, by which a pulverulent product is sepa- 

 rated, which is thoroughly washed and dried. This body con- 

 sists of dinitric starch in two molecular modifications : one of 

 these is insoluble in strong alcohol, but soluble in a mixture 

 of alcohol and ether ; the other, isodinitric starch, is soluble in 

 alcohol. The composition of both is expressed by the formula 

 C l2 H 8 8 2N0 5 . 



These substances when heated give off red vapours and de- 

 flagrate ; the mononitric compounds are more stable than the 

 dinitric ; and the insoluble modification more so than the 

 soluble. 



When one of these compounds is heated with protochloride of 

 iron the starch is regenerated, binoxide of nitrogen is liberated, 

 and peroxide of iron deposited. The reaction in the case of 

 the mononitric compound is this : 



C 12 H 9 9 N0 5 + 6FeCl + HO = Fe 2 3 + 2Fe 2 Cl 3 + N0 2 + C ,2 H 9 9 HO. 



The body produced has all the properties of ordinary soluble 

 starch. 



Soluble starch is strongly dextrogyrate ; and the nitric deriva- 

 tives are also dextrogyrate, but with an intensity decreasing with 

 the quantity of nitric acid in the compound. 



M. Bechamp considers these compounds as nitrates analogous 

 to nitrate of potash or nitric ether. 



The formula of quinine, G 20 H 24 N 2 O 2 , only differs from that 

 of cinchonine, G 20 H 24 N 2 O, in containing one atom more oxygen. 

 The same relations obtain as between glycolic acid, € 2 H 4 O 3 , and 



