POTASH. 273 



greatly in quality. Potash after it has been sub- 

 jected to this burning is the pearlash of commerce. 

 This, when good, is perfectly white and bears a 

 uniform appearance. In converting; the potash into 

 pearlash particular care should be taken to prevent 

 its fusion, as the extractive matter would not then 

 be perfectly consumed, and the alkali would form so 

 intimate a union with the earthy particles that it 

 could not readily be dissolved. 



The numerous and vast forests in many of the 

 Russian provinces have given rise to the manufacture 

 of potash, which is pursued there to a great extent, 

 it being a very ancient and considerable branch of 

 industry in Russia. A large quantity of this alkali 

 is annually exported thence. It is prepared princi- 

 pally from the ashes of the oak and all the species of 

 pine. The consumption of wood as fuel is very 

 great, and the ashes of this are collected and used in 

 the manufacture of potash. Among the numerous 

 fabrics erected for the purpose some belong to the 

 crown ; large works of this kind are established at 

 Tolskoi-Maidan. The production of the ashes forms 

 no part of the process carried on ; these are purchased 

 from the peasantry who deliver them at certain fixed 

 prices. The works contain thirty-two ash-pits, four 

 boilers, and a calcining furnace for making pearlash. 

 In an establishment on this scale, the whole being 

 in constant activity, three hundred casks, each cask 

 containing twenty poods (720 Ibs. Av.)> are annually 

 produced. 



England is supplied with potash and pearlash 

 principally from Canada, where the abundance of 

 wood renders the manufacture a matter of little 

 difficulty or comparative expense. 



Besides the quantity of wood burnt for the sole 

 and express purpose of obtaining their ashes, a 

 large proportion of potash is produced, as in Russia, 



