Account of a new Wood for Dyeing. 93 



vations refpe&ing the bark may be applied alfo to the wood ; 

 tor, though the latter produces a different colour, it exhibits 

 almoft the fame phenomena as the bark. 



If the bark be boiled in water, the coloured extract thence 

 refulting, when expofed to the action of the fulphuric, muri- 

 atic and nitric acids, refifts them much longer than an ex- 

 tract of brafil or logwood. The colour, after being deftroyed 

 bv a combination of acids, may be revived by the means of 

 alkalis. 



Vinegar, lemon-juice, and tartar render this dye more 

 brilliant, and communicate to it a fine rofe colour, while 

 thefe acids, on the other hand, deftroy the colour of brafil 

 and logwood altogether. 



The feculae of the bark of the paraguatan attach them- 

 felves and adhere to woollen, cotton, and filk. The colour 

 is more brilliant on filk than woollen, and more brilliant on 

 the latter than on cotton. 



The fame feculae dried may be afterwards diffolved in 

 alcohol, and communicate to it a tint fimilar to that obtained 

 from cochineal. 



By mixing alum with a highly concentrated decoction of 

 the fame fubftance a fpecies of lake may be produced, but 

 neither fo lively nor fo pretty as that obtained from cochi- 

 neal by a like procefs. 



The fame decoction mixed with that of gall-nuts furnifli- 

 cd me with a precipitated pigment of a weak rofe-colour. An 

 infufion of brafil or logwood, mixed with an infufion of 

 galls, affumes a darker and browner tint; mine on the other 

 hand became clearer by it, and aflumed a delicate rofe colour, 

 or. one fomewhat fimilar. 



It mull indeed be acknowledged, that the dye extracted 

 from the paraguatan has not a ftrength equal to that of co- 

 chineal. It is however fuperior to thofe of madder, brafil 

 and logwood, fince it refifts vinegar, lemon-juice and tartar. 

 Soap even does not deftroy it fo fpeedily as it does thofe of 

 brafil and logwood. 

 The bark is attended with this advantage, that by employing 



it 



