26 On the Manufacture of Saltpetre. [Jan. 
manufacturers are aware of this fact, but not being able to account for 
it on scientific principles, they say, that saltpetre generates or developes 
saltpetre ; but I dare say that most scientific men will concur with me, 
that the above idea of the natives is next to a physical impossibility. 
Owing to the porous nature of the earthen crystallizing vessels, a part 
of the saltpetre liquor oozes through the bottom, and is absorbed by the 
earth on which the utensils are placed, occasionally they are broken, 
and the contents of course falls into the earth below. This earth is 
again subjected to the process of filtration, and the practice of the 
manufacturer, in order to obtain what had been wasted in the above 
manner. Thus the loneaks proceed from season to season, without 
the least deviation or alteration in their manufacture. No persuasion, 
however reasonable, by way of improvement, will cause them to alter 
the plans which their forefathers had in practice ; and it is probable, that 
the methods used at present were the same three thousand years ago. 
The saltpetre obtained in the above manner, which I have attempted 
to describe, is a very impure article, termed by the natives dhoah, and 
is sold at the rate of from two to three rupees a maund. It generally 
contains from 45 to 70 per cent. of pure nitre. The following analysis 
was tried from an average of several hundred maunds of what was 
stated to be of good quality, and brought three rupees eight annas per 
maund. 100 grains operated upon. 
Insoluble matter, sand, andmud,.............. 5.0 
Sulplatetorsoday Vel Mh BOUEE a eRe ey 9A 
Miuriatetordoc. .’ p. Sher ty, ar eet eee Sree ae 8.0 
Rotel anmpmrbyen goer ie oa RE ode ou eae 22.1 
Lcd eran Ree Sete cee 5k A TE, Pe eee OE eee he fe) 
100.0 
This may be taken as a fair sample of the quality that the loneahs 
produce in general, but when it passes from their hands to the saltpetre 
merchants, it is frequently adulterated with sand, mud, and dirty salts 
of various kinds, to such a degree, that it scarcely contains 50 per cent. 
of pure nitre. A sample of this adulterated article from 15,000 maunds 
gave me the following result : 
Insoluble matter, sand, and mud,./............ Oot 
Dil plate Ol sOta,, 5,0. meee te taere seh aie ces alas 23.8 
Wiuriate lo: do... eee ee. cr aie ee ee 4.2 
Total witperity se. SA ens Se aE 50.7 
Nat Gre: boos. Jeet. oti tsel. dante, ives Bere 49.3 
