fir Ihe Vfe of Ar lifts, Manilfaaurers, &c.' 1^7 



To obtain it perfeftly pure, or to rectify it, put it again 

 into a retort; and having added to it a little diffolved alkali, 

 in order to abforb the acid, place it in a very gentle fand- 

 bath, and adapt to it a receiver. If the haff of it be then 

 driven over at a very gentle heat, you will obtain very pure 

 eether. 



What remains after the firft diftillation confifts, for the 

 mod part, of i'ulphuric acid impregnated with fulphurous gas 

 and with carbonaceous matter furaiflied by the decompofition 

 of the alcohol. 



This refiduum mav be again employed for the prepsration 

 of £Ether. For thi* purpofe pour over it good fpirit of wine^ 

 but always a third leis than before, and proceed to diftilla- 

 tion: if you then reftify. you will obtain good Eether. 



Another good Procefs for Gliding. 



iEther is proper, as has been above remarked, for taking 

 up gold from the nitro-moriatic acid. Thofe to whom this 

 preparation of astlier, for the purpofe of gilding, appears too 

 difficult, mav ufe in its ftead eflTential oils, fuch as fpirit of 

 turpentine, oil of lavender, and the like; which will alfo take 

 gold from its foKilion. 



To prepare the Alcohol. 



As it is fometimes difficult to procure alcohol ready pre- 

 pared, the follouino: method of reclifving \veak fpirit of wine 

 will be found very advanlaceous to artifts : 



Take well dried potafli and pour over it fpirit of wine : the 

 latter will not unite with the potafli, but the water which it 

 may contain will be taken up by that alkali. The fpirit of 

 wine is then to be poured into another glafs, and fubjeftcd 

 to the fame operation as before. This procefs is to be re- 

 peated till it is obferved that the potafli is no longer verv 

 moid. Such fpirit of wine is exceedingly fi:rong, but rendered 

 a little impure bv the potafli, as will appear from its yellowifli 

 colour. It muit therefore be poured into a retort, having a 

 receiver adapted to it, and dillilled to a fifth part over a flow 

 heat. What conies over is alcohol. 



Cold Gilding of Silver, 



Bcfides the above methods of gilding, there is alfo a cold 

 gilding of filvcr, which can be fpeedily done, and with little 

 trouble. 



Ditrolve gold in the nitro-muriatic acid, and dip fome linen 

 rags in the folulion ; then burn them, and carefully ]iieferve 

 the aflics, which will be very black, and heavier than com- 



k % niou. 



