Manufacture of Pot and Pearl Ashes. 3035 
its a most elegant appearance of liquid fire. It resembles 
exactly melted iroh, and exhibits the same appearance when 
poured from one vessel to another. During this stage of 
the process, if a candle or lighted torch, be brought in con- 
tact, or nearly so, with the surface, the gaseous matter float- 
ing over it inflames, and burns over its whole surface, with 
a bluish flame, like hydrogen gas. 
This substance, now in a state of fusion, is poured by 
means of Jarge iron ladles into iron pots, or kettles, and al- 
lowed to cool in cakes. The cakes, when broken, exhib- 
it a fracture like loaf sugar, being of a granulated structure. 
The appearance of the fracture, as to colour, is different in 
different parts of the mass; exhibiting in its course every 
shade of the rainbow, but less concentrated and glowing. 
This is the pot ash of commerce. It is more deliquescent 
than pearl ashes, andI should think more caustic. During 
the evaporation of the ley, a salt is precipitated, of a grey- 
ish colour, shaped much like crystals of sulphate of magne- 
sia. This the boilers call nitre, and most of them are care- 
ful to scrape it out from the kettles by means of ladles, and 
to replace it on the leeches with the ashes, as they suppose 
it to retard the process of melting. 
Ifit be intended to make the pearl ash, the mass obtained 
by evaporation, which in the language of the country is cal- 
led “‘black salts,” is taken from the kettles and exposed 
to a high temperature in a large oven-shaped furnace, under 
which is an arch so constructed that the flame plays back 
upon the salts. This process is carried on till the mass’ 
originally black becomes of a handsome white. The mass is 
keptin agitation by means of an ironrod. ‘The substance 
described in the books as potash, is the substance termed 
by the manufacturer, ‘‘ black salts,” in which state, so far 
as I know, it is never seen in market. It is the substance [ 
have described, which is exported from this country to Eu- 
rope. 
Vou. VITI.—No. 2. 39 
