322 Intelligence and Miscellaneous Articles. 



ON THE COMPOSITION OF ORCINE AND ITS DERIVATIVES. 

 BY MM. LAURENT AND GERHARDT. 



Chemists generally admit the formulae proposed some years since 

 by M. Liebig, for dry and crystallized orcine. According to this 

 chemist, they are — 



Dry orcine C ,6 H><»0 4 



Crystallized orcine. . C 16 H 16 4 + 3Aq. 



These formulae seem at first to agree perfectly with the metamor- 

 phoses by which orcine originates, and especially with the production 

 of orcine by lecanorine. But if the formulae of M. Liebig be com- 

 pared with the analyses of M. Dumas, and with the more recent ones 

 of MM. Will and Schunck, whose results are almost identical with 

 those of M. Dumas, it will be seen that these formulae suppose an 

 error of nearly 3 per cent, in the carbon found by experiment in dry 

 orcine. 



Struck with this circumstance, one of the authors proposed two 

 years since to reject the formulae of M. Liebig, and to replace them 

 by the following : — 



Dry orcine C? H s O 2 



Crystallized orcine .... C 7 H 8 O 2 + Aq. 



These not only agree very well with the analyses of orcine, but also 

 with those of lecanorine and other crystallizable derivatives. 



MM. Laurent and Gerhardt state that they have lately obtained 

 with orcine a new derivative, the composition of which confirms the 

 latter formula?. This compound is bromorcine, a substance which 

 crystallizes in fine silky needles, and is easily produced by the action 

 of bromine on orcine. The formula of bromorcine is C 7 H 5 B 3 O' 2 , 

 and it consequently represents orcine, in which three equivalents of 

 hydrogen are replaced by three equivalents of bromine. It is re- 

 markable that potash dissolves it immediately, and becomes of a very 

 deep violet-brown colour. It was found to contain 23" 1 per cent, 

 of carbon, the authors' formula requiring 23*2. If the proportions 

 of M. Liebig were supposed to be correct, the authors state that they 

 must have committed an error of nearly 2 per cent, in the same way 

 as M. Dumas in his experiments on normal orcine. 



The authors' formulae place orcine in relation with the salicylic 

 series ; they form an isomeric with the saligenine of M. Piria. The 

 following are the relations which exist, according to MM. Laurent 

 and Gerhardt, between orcine and its crystallizable derivatives. 



Lecanorine : by ebullition with barytes water, it gives carbonate 

 and orcine : — 



C 16 H 14 7 + H 2 0:=2[C0 2 +C 7 H 8 2 ]. 

 lecanorine orcine. 



Pseuderythrine : by boiling with alcohol and an alkali, lecanorine 

 gives carbonate, orcine and pseuderythrine : 



C 16 H 14 O7 + C 2 H6O=CO 2 +C7H 8 O 2 + C 10 H ,2 CH. 

 lecanorine alcohol orcine pseuderythrine. 



