Experiments on Staining Wood. 53» 



experiments on the ftaining of our own wood, in order to 

 render them equal, if not to all foreign woods, at lead to 

 fome of them, firffce many things can be coloured iri thai 

 manner which are harder and more compact than wood. 

 The labours of Du Fay in this refpecl are well known ; and 

 it appears by fome papers of his among the Memoirs of the 

 Academy of Sciences, that rock cryftal, when expofed to the 

 vapour of arfenic and antimony, affumes a red colour. Count 

 de Borch's defcription of the method of ftaining marble in 

 Italy may alfo be mentioned ; and the procefs by means of 

 the fmoke of oak chips, which is employed by the Dutch 

 for colouring their tiles and earthen-ware. Canes are pre- 

 pared for ufe in India, by clipping them in quicklime. That 

 hard compact wood brought from America, and particularly 

 Guiana, which, on account of its variegated and fpottcd ap- 

 pearance, is called Bois de Lettres, and which Aublet, who 

 gives it the name of PiratincraGuianenfis, much admired, has 

 its whole fin-face ftained bv the Indians with the blackeft and 

 nioft .durable colours. — As the art of ftaining wood feems at 

 prefent to be nearly loft, the following experiments may b& 

 ■of fome utility to artifts : 



I. By Means of Oils and Acids. 

 . Exp. I. A fquare piece of plane-tree wood, a line in thick- 

 nefs, was put into pounded dragon's blood fron the Cana- 

 ries * mixed with oil of turpentine, and placed o- r the fire 

 in a glafs teflel, The wood ilow'y affumed the co!o r, even 

 before the fpirit was volatilifed. After more than an hour 

 the veflcl was taken from the fire and fuffered to ftand the 

 whole night, when the wood appeared of a mahogany co- 

 lour, not merely on the furface, but alio in the interior parts. 

 The denier fibres were fomewhat lefs coloured, but this, in? 

 of injuring the beauty of the wood, rather added to it. 

 'J be red dye can be made ftronger or weaker by taking a 

 greater or lefs quantity of dragon's blood, and by a greater 

 T:.at from Mutbgafcar is of an inferior quality. 



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