138 



CARBONIZATION OF TURF. 



Oily products. 



the process, finishing it with one fourth of well burning 

 wood ; and this earthen ware will be equal to what is com- 

 monly made for domestic purposes, as I have found by ex. 

 perience. 



To obtain such results, I have myself constructed a fur- 

 nace on the principles laid down above. Neither was the 

 preparation of the earth for each kind of pottery forgot- 

 ten : this was the basis of my labour.* 



I have already observed, that the oily products received 

 in the condenser might be turned to advantage. These pro- 

 ducts are frequently divided into two strata: the first water, 

 impregnated with a small quantity of a light oil, and con- 

 taining acetous or acetic acid : the second a black, heavy, 

 acrid, very penetrating oil, thick like tar, and difficult of 

 solution. This may be used for various purposes. 

 Acid useful for The rectification of these oils furnishes a certain quantity 



making iron- f ac j ( i by means of which I have prepared the solution of 

 liquor, for dyers . . ... . 



or calico print- iron, called in manufactories iron liquor ; but it is proper 



ers > to add a little concentrated acetous acid, in order to pre- 



vent the precipitation of the iron in the state of oxide. — 

 With a solution of this sort I have prepared by a particular 

 method patterns of black, on cotton, silk, and woollen, 

 which were not inferior to those dyed in the usual way. I 

 could likewise produce very good nankins ; and the buffs on 

 printed calicoes might be prepared Avith iron dissolved in this 

 acid, thickening the composition with starch or gum, ac- 

 cording to the value of the article and the tint required. 



What I have said respecting iron dissolved in the acetous 

 acid may be extended to the employment of the cmpyreu- 

 matic oil in dyeing wool, &c. and a number of other pro- 

 cesses, too many to enumerate. 



Lastly, I am persuaded, that it is possible to oxide cop- 

 per by means of this acid, which however is afforded in 

 smaller quantity perhaps by turf than by wood. 



and manufac- 

 turing verdi- 

 gris. 



Improvement 

 in tiles. 



* I would beg leave to mention an improvement I proposed in 

 tiles, and which I carried into execution. This consists in making 

 a tongue to them of a triangular shape, the base being very large 

 and at bottom ; and with respect to the moulding, it may be suffi- 

 cient to say, that two men could do the work of four in a given 

 time. 



To 



