498 



HISTORY OP THE VEGETABLE KINGDOM. 



of alum is added, to render its colour less fugi- 

 tive. 



Brazil-wood boiled in water communicates 

 to it a fine red colour, while the wood itself 

 becomes of a darker colour, and if the ebullition 

 be continued long enough the residuum will be 

 black. Paper tinged red with this decoction is 

 altered to a violet colour by the action of the 

 alkalis, and to a yellow by most of the acids. 

 The action of sulphuric acid gas renders it quite 

 wliite. M. De Bonsdorff, in the "Annales de 

 Chimie et de Physique," details many phenomena 

 of the effects which this colouring matter has 

 on different acids. It is an excellent test to 

 detect the presence of sulphuric acid in vinegar. 

 In pure acetic acid it receives only a violet tinge, 

 but the admixture of only one two-hundreth 

 part of sulphuric acid will give the stained paper 

 a yellowish instead of a violet hue. 



In two decoctions made with equal weights 

 of madder and of Brazil-wood, only half the 

 quantity of chlorine gas, which will destroy the 

 colour of the madder, is required to produce a 

 like effect on the Brazil-wood. More colour is 

 extracted from this wood by alcohol than by 

 water. Warm marble stained by the spirituous 

 tincture assumes a purplish red colour, which, 

 on the heat being increased, changes to a violet 

 hue. If the stained marble be covered with 

 wax and considerably heated, the colour changes 

 through all the shades of brown, and at last 

 becomes fixed of a chocolate hue. 



A fine crimson red lake is prepared from this 

 colouring matter by precipitating it when in a 

 state of solution with alum. The average 

 annual quantity imported for the last five years 

 is 9.50 tons. Its price has very much fallen off, 

 differing from £65, in 1826, to £35 per ton in 

 1830. A duty of £2 per ton is charged on the 

 importation of Brazil-wood. 



A species of this tree grows in the West 

 Indies, the wood of which is known in commerce 

 as Brazill^tto. It is of the same kind, but of 

 very inferior quality to the Brazil wood. The 

 duty charged on its importation from British 

 possessions is only Ss. per ton, and in consequence 

 it can be obtained on much cheaper terms than 

 that from South America. Some years ago the 

 demand for it was so great that it was cut down 

 with unsparing hand, and scarcely any of the 

 large trees were left in the British plantations. 

 This species is known to botanists as cwsalpinia 

 vesicaria ; it never attains to so large a growth 

 as the ccesalpinia crista. Its branches are slen- 

 der and full of small prickles ; the flowers are 

 white, growing in a pyramidal spike at the end 

 of a long slender stalk. 



Sapan-wood is another dyeing substance 

 obtained from another species of the same genus. 

 It is distinguished as ccesalpinia sapan. The 

 flowers of this and the vesicaria have ten 



stamina; those of the crista Lave only five. 

 There is scarcely any consumption of this wood 

 in England ; very few tons being annually 

 imported. Its price averages from ten to six- 

 teen pounds per ton, and it is admitted on a 

 duty of fifteen shillings per ton. 



The same duty is charged upon Nicaragua or 

 Peach wood, which is another kind of Brazil- 

 wood. It dyes a bright fugitive red, called fancy 

 red. Though not so rich in colouring matter as 

 the Brazil, it yields a colour which is brighter, 

 more delicate, and more beautiful. 



It takes its name from the Gulf of Niacaragua 

 in America, opposite to Providence island, 

 whence it was first imported into England. 

 Dampier says this was the only place on the 

 Atlantic where he saw the tree ; but that on the 

 South-sea side of the American continent it 

 grew abundantl3^ In his time Nicaragua-wood 

 was sold at £30 per ton, being double the price 

 of Logwood. 



The average importation for the last five years 

 is much more considerable than that of Brazil- 

 wood, being 1766 tons. The price of the best 

 is about £15. 



Cam-wood is another red dj^e-wood, obtained 

 from the Brazils, and also from Africa. It once 

 grew commonly in the neighbourhood of Sierra 

 Leone, and was found at Tonquin and other 

 parts of Asia. This wood is of a very fine col- 

 our ; it is principally used in turnery for the for- 

 mation of handles of knives and other similar 

 articles. A very small quantity of Cam-wood 

 is imported into this country, averaging annu- 

 ally not more than 400 tons. It is admitted at 

 the same duty as the sapan. Bar-wood is also 

 liable to the same duty, and is not brought more 

 abundantly into England. This is likewise a 

 red dye-wood of Africa. 



Indigo ( Indigofera ) . Natural family leciu- 

 minosm ; diadelphia, decandria, of Linnaeus. 

 There are not less than twenty-four species of 

 this genus enumerated, all natives of tropical cli- 

 mates. In Hindostan, China, Japan, the south- 

 ern parts of Africa, America, Java, and Mada- 

 gascar, the various species of this plant grow in 

 a wild state. The three species chiefly cultivated 

 for the production of the blue dye, are the East 

 Indian (Indigofera tinctoria); the West Indian 

 (i. anil); and the Silver-leaved (i. argenica). 

 The East Indian,which is that most largely culti- 

 vated, is not so hardy, nor is its pulp so good as 

 the others ; but it yields a larger produce, and 

 on this account is preferred. 



The West Indian plant grows much higher, 

 and is hardier than the tinctoria, while the silver- 

 leaved or wild indigo, is hardier than either of 

 the other two, and yields the finest pulp, though 

 in least quantity. They are all rather elegant 

 little shrubs, and all yield more or less indigo. 



The East Indian plant (ind. tinctoria J has a 



