f 41> j 
LXXXHI. Process of prepuring Saltpetre, and Mode of ma-- 
nufacluring Gunpowder, in Ceylon*. 
Tue preparing of saltpetre, and the manufacture of gunpow- 
der, are arts which the Singalese, for many years, have constantly. 
practised. The process of preparing the salt in different parts 
of the country was very similar. When the salt occurred im- 
pregnating the surface of the rock, as in the cave near Memoora, . 
the surface was chipped off with small strong axes, and the 
chippings by pounding were reduced to a state of powder. This 
powder, or the loose fine earth, which, in most of the caves, 
contained the saline impregnation, was well mixed with an equal, 
quantity of wood-ash. The mixture was thrown on a filter 
formed of matting, and washed with cold water. The washings 
of the earth were collected in an earthen vessel, and evaporated 
at a boiling temperature, till concentrated to that degree that a 
drop fet fall on a leaf became a soft solid. The concentrated 
solution was set aside, aud when it had erystallized, the whole 
was put on a filter of mat. ‘The mother-lye that passed through, 
still rich in saltpetre, was added to a fresh weak solution, to be 
evaporated again; and the crystals, after having been examined, 
and freed from any other crystals of a different form, were either 
immediately dried, or, if not sufficiently pure, redissolved and 
crystallized afresh. ‘The operations Just described, were generally 
carried on at the nitre caves. In the province of the Seven 
Korles, besides extracting the salt at the caves, the workmen. 
brought a quantity of the earth to their houses, where keeping 
it under a shed protected from the wind and rain, without any 
addition excepting a little wood-ash, they obtain from it every 
third year a fresh quantity of salt. 
In their mode of manufacturing gunpowder, which is very 
generally - understood, there is not the least refinement. To 
proportion the constituent parts, scales are used, but not weights. 
The proportions commonly ensployed are five parts of saltpetre, 
and one of each of the other ingredients of sulphur and charcoal. 
The charcoal preferred is made of the wood of the parwatta tree. 
The ingredients moistened with very weak lime-water, and a. 
little of the acrid juice of the wild yam, are ground together 
between two flat stones, or pounded inarice mortar. | After the . 
grinding or pounding is completed, the most seminated is col- 
lected, and carried in baskets to an adjoining stream, where it . 
is well washed; the lighter particles are got rid of by a rotary 
motion given to the basket in the operation; and the residue, 
still wet, is transferred to shallow baskets for careful examina- 
tion, 
* From Dr. Davy’s Ceylon, 
LXXXIV. On 
