July 1, 1865.] THE TECHNOLOGIST. 



METALLIC COINS TO SUPERSEDE COWRIES IN AFRICA. 545 



added to the list, and the use of Mordants became general. "We do not, 

 as would naturally be supposed, derive our dyes from the brilliant, and 

 varied colours of plants, for it is found that in those parts of the plant 

 exposed to free air and light, though the colour is brilliant yet it is 

 small in quantity and soon lost. Most vegetable dye colours are 

 obtained from the roots, bark, and berries of plants, which exhibit in 

 their natural state but little of the beauty which is obtained from them 

 by the chemist and dyer. The colours obtained from plants are chiefly 

 yellows, browns, and blues ; no proper black has yet been obtained. 

 These are not soluble in water, but require spirits of wine, alkalies, or 

 acids, to dissolve them. 



Animal and vegetable tissues and fabrics possess a great attractive 

 power for all colouring matter, whether animal, vegetable, or mineral. 

 The common iron-mould stain is a very good example of the attractive 

 influence of fibre for mineral colour — the iron having combined with 

 the vegetable fibre remaining fixed, no washing will remove it. Dyeing 

 materials may be classified into two groups : — 1st. Colours capable of 

 imparting permanent tints to various textures without the assistance of 

 any other substance, these being called substantive colours. 2nd. Colours 

 which cannot be permanently imparted without the assistance of a 

 second body, these being termed adjective colours. 



METALLIC COINS TO SUPERSEDE COWRIES IN AFRICA. 



The following letter from Lord Alfred Churchill to the Secretary ot 

 State for the Colonies, deals with an important subject : — 



The Council of the African Aid Society have had under their consi- 

 deration the necessity and advantage of finding some metallic substitute 

 for the cowries, hitherto in use among the natives. 



A currency ought to be adapted to all the wants and habits of the 

 people for whose use it is intended. Cowries, as a circulating medium, 

 nave been for a long time in use in the countries of the Bight of Benin 

 and the Niger territories. Since the annexation of Lagos to the 

 British Crown, all the English coins have been introduced there. 

 They are coming into use among the natives, but do not suffice for the 

 general wants of that portion of the community. The lowest English 

 coin in circulation is the farthing. The value of this is thirty cowries. 

 But a great many articles of daily consumption are purchased much 

 below that price. Unless, therefore, some smaller coin be introduced, 

 cowries cannot be abolished or replaced as a circulating medium. In 

 the interests of progress and civilization, of which Lagos is an outpost, 

 it is desirable that the currency should be solely metallic. 



