QUERCUS CORTEX. 335 



cinnamic acid, cinnamate of cinnamic-cether (styracin), and various 

 resins. Cinnamic acid, C 9 H 9 2 , which occurs also in the 

 balsams of Peru and Tolu, is a colourless, odourless, crystalline 

 body, closely allied to benzoic acid, being excreted in the urine 

 partly as hippuric acid. 



Dose.?> to 20 gr. 



Storax is contained in : 



Tinctora Benzoini Composita^ 33 gr. in 1 fl.oz. 



ACTION AND USES. 



Storax is a local and remote stimulant, antiseptic, and 

 disinfectant, like benzoin and the balsams of Peru and Tolu. 

 It is used for scabies and phthiriasis. 



ULMACE^B. 



Ulmi Cortex ELM BARK. The dried inner 

 bark of Ulmus campestris. Broad-leaved Elm. From 

 trees indigenous to and cultivated in Great Britain. 



Characters. A tough brownish-yellow bark, about half 

 a line thick, without smell ; taste mucilaginous, slightly bitter 

 and astringent. 



Composition. Elm bark contains about 3 per cent, of tannic 

 acid, 20 per cent, of mucilage, and a peculiar brown body, ulmin, 

 insoluble in water. 



Incompatibles. Persalts of iron, salts of lead and silver, 

 and gelatine. 



Preparation. 



Decoctum Ulmi t 1 in 8. Dose, 2 to 4 fl.oz. 



ACTION AND USES. 



Elm bark has a similar action to oak bark and tannic acid, 

 but is demulcent as well as astringent. 



CUPULIFER^. 



Quercus Cortex OAK BARK. The dried bark 

 of the small branches and young stems of Quercus 

 pedunculata. Collected in spring, from trees growing 

 in Great Britain. 



Characters. Covered with a greyish shining epidermis, 

 cinnamon-coloured on the inner surface, fibrous, brittle, and 

 strongly astringent. 



