QUASSIA 227 



(m.pt. 209 to 212), which are to be regarded as the active con- 

 stituents ; it contains, further, a very small amount of a crystalline 

 bitter principle melting at 234, as well as a minute quantity of a 

 yellow crystalline substance which exhibits in acidified alcohol a 

 magnificent blue fluorescence. It contains no tannin. 



Use. Quassia is used as a pure bitter tonic. It is also largely 

 used for the preparation of horticultural insecticides and non-poisonous 

 fly papers. Cups turned from the wood were formerly in use under 

 the name of bitter cups. 



Substitutes. Surinam quassia is usually in smaller billets than 

 Jamaica quassia ; it is best distinguished by its microscopical 

 characters, most of the medullary rays being one cell wide, whereas 

 in Jamaica quassia they are two or three cells wide ; the wood 

 parenchyma is free from crystals of calcium oxalate, which are 

 contained in Jamaica quassia. The width of the medullary rays 

 and the presence of calcium oxalate are therefore specified in the 

 Pharmacopoeia in order to exclude Surinam quassia ; for although 

 the physiological action is presumably the same, it is desirable for 

 the sake of uniformity to use one variety of the wood only. 

 The bitter principles contained in Surinam quassia are distinct 

 from those of Jamaica quassia, and have been called ' quassiins ' 

 (Massute, 1890). 



Quassia chips that have been exhausted and re-dried yield less 

 aqueous extract (2*7 as compared with 6*3 to 8' 6 from genuine wood) 

 and are less bitter. 



LOGWOOD 



(Lignum Hsematoxyli) 



Source, &c. The logwood tree, Hcematoxylon campechianum, 

 Linne (N.O. Leguminosce) , is a tree of moderate size, indigenous 

 to Central America, but naturalised in the West Indian Islands. 

 The use of the wood as a dye was probably known to the Mexicans, 

 for its introduction into Europe followed closely on the conquest 

 of Mexico by Cortes ; in 1746 it was introduced into the London 

 Pharmacopoeia as a mild astringent, but is now not much used 

 medicinally. 



The wood is exported in the form of billets and logs from which 

 both bark and sapwood have been separated ; the heartwood alone 

 contains the colouring and astringent principles. 



Description. The logwood of commerce consists of the heartwood 

 of the tree, and is imported in logs and billets from 6 to 15 cm. in 

 diameter and 1 to 2 or more metres in length. Externally these 

 are of a dull dark orange or purplish red colour, internally they are 



