168 Observations on the Manufacture of Pot Ash 



for that will congeal and crystalize with hot \Yater in the 

 same quantity as with cold water ; which is not the case 

 with any other neutral salt or alkaH. If after all, 

 from any circumstance unforeseen, the lies shall not ap- 

 pear pure and clean, after taken from the last sedi- 

 ment, they must stand quiet until another is form- 

 ed; or until it appears, that no other will form. Should 

 one form, it must be separated as before, prior to its being 

 put into the kettles for the last operation. Without these 

 precautions, the pot ash, in consequence of neutral salts, 

 and a chalky matter which are obtained from the ashes, 

 vrill be hard to flux; and require a long time to effect it; 

 which will greatly endanger the kettles; and after it is 

 fluxed, will be very impure ; and sell for a reduced price, 



if the owner be fortunate enough to find a market at any 

 rate. 



The pot ashes which I have examined, that have been 

 condemned by the assay masters, I have found to contain 

 principally common earth; which is undoubtedly the chief 

 source of impurity in the pot ash of this country. If any 

 crystals of common salt or nitre appear in the sediment, 

 they may be preserved and purified by an easy process, which 

 is known to people in general, who have attended to the 

 manufacturing of saltpetre. 



After the lie is properly cleared from earthy matter, and 

 common salt, which not only retards the fluxing process, 

 as has been observed, but renders it unfit for many uses, 

 particularly the bleaching of linens ; it must continue boiling 



until 



