TANNIN IN CLOVES. 



215 



gallotannic acid. The factor is only used provisionally to afford a 

 means of comparison. 



It appeal^ from these experiments that cloves contain about 10 or 

 12 per cent, of tannin calculated as gallotannic acid, that clove stems 

 contain about 8 per cent., and that allspice contains 5 or 6 per cent. 

 of tannin so calculated. It is also evident that the quantity of 

 tannin is a valuable criterion of the quantity of cloves contained in 

 an adulterated sample. 



The large quantity of permanganate required by the oxidizable. 

 matters other than tannin is remarkable in the case of cloves. It is 

 in every case much larger than that required to oxidize the tannin. 

 I hope to be able to make a further investigation on the nature of 

 these substances at a future time. 



