Tans and Dyes 



353 



pieces or ground to a coarse powder. Wattle bark is largely used in the United Kingdom for 

 tanning sole leather. It yields a firm, solid leather with a faint pink tint. 



DlVI-DlVI 



This material consists of the dried husks of the pods of a leguminous tree, Ccesalpinia 

 coriara, indigenous to 

 Central America and 

 cultivated in South 

 America, and, on a 

 small scale, in Java, 

 India, and Australia. 

 In preparing it for the 

 market the pods are 

 split open, and the 

 husks, which are similar 

 to those of an ordinary 

 pea pod, are spread out 

 in the sun until they 

 become hard, brown, 

 and dry. 



Sumac 



This well-known and 

 valuable tanning mate- 

 rial consists of the dried 

 leaves of Rhus coriara, 

 a shrub cultivated in 

 Sicily and growing wild 

 in Austria and the Bal- 

 kans. The plant thrives 

 on sunny slopes of dry, 

 stony, and barren soil ; 

 it is usually grown from 

 shoots and develops 

 rapidly. Plucking of 

 the leaves may be com- 

 menced in the second, 

 but preferably in the 

 third year, and after 

 fifteen years' growth the 

 shrubs cease to yield 

 leaves rich in tannin and 

 should be replaced. The 

 leaves are usually dried 

 and ground several times 

 in stone mills to produce 

 a fine powder for export, 

 seven per cent, of tannin. 



Photo by Sir Harry Johnston, K.C.M.G., K.C.B. 



MANGROVE SWAMP 



' By permission oj Messrs. Hutchinson 



Good Sicilian sumac contains from twenty-three to twenty- 

 Sumac is used for the production of soft, light-coloured, mild 

 leathers, and is almost indispensable at present for tanning such materials. It is also ver}' 

 largely employed for improving the colour of leather tanned with cheaper, dark-coloured 

 materials, such leather being usually given a final dressing in a hot sumac solution. 



24— C.P. 



