248 QUEECUS EOBUE 



of oak bark. The bitter, colourless, crystallizable, neutral sub- 

 stance, described by Gerber, in 1843, and named quercin, requires 

 further examination ; the recent experiments of Eckert failed to 

 detect it in young oak bark. Besides querci-tannic acid, oak 

 bark also contains a small quantity of gallic acid, pectin, and 

 other vegetable and inorganic constituents. 



Medical Properties and Uses. The effects of oak bark are 

 similar to those of other vegetable astringents containing tannic 

 acid. It is, however, but little employed as an internal remedy, 

 although in the form of a decoction it has been found very useful 

 in chronic diarrhoea, in the advanced stages of dysentery, and in 

 alvine haemorrhages, &c. But the decoction is chiefly used as a 

 local astringent in the form of a lotion, gargle, or injection, for 

 various purposes, as in indolent ulcers, relaxed sore throat, 

 leucorrhcsa, &c. Poultices of the powdered bark have also been 

 applied with advantage to gangrenous and ill-conditioned ulcers. 



The chief use of oak bark is not for medicinal purposes, but 

 for tanning leather, for which purpose it has always been largely 

 employed. It has also been used for the preparation of inks, and 

 for other purposes. 



Besides the bark the wood of this tree is well known as forming 

 most valuable timber; and the fruits (acorns) have been also recom- 

 mended as food for cattle, but recent experience would seem to 

 show that in some cases at least, they act injuriously. 



Per. Mat. Med., by B. & E., p. 492; Pharmacographia, p. 534; 

 BentL, Man. Bot., p. 634; Steph. & Church., Med. Bot., by 

 Burnett, pi. 151 ; Watts' Diet. Chem., vol. v, p. 8 ; Bloxam's 

 Chemistry, 3rd edit., p. 585. 



DESCRIPTION OP PLATE. 

 Drawn from a tree in the Eoyal Gardens, Kew. 



1. A young branch with male and female flowers. 



2. Portion of male catkin. 



3. An anther. 



4. Female flowers. 



5. Section of ovary. 



6. Eipe fruit. 



7. Acorn removed from the cup. 



8. Seed, with one cotyledon removed. 



(2-5 enlarged.) 



