59 
Compound Sulphuret from Huel Boys. 
the results of observation, as nearly as our means of deter- 
mination authorise us to expect, we are warranted in believing 
that the principle of nature is obtained, as we then have all 
the proofs of its being so, which men can have of the justness 
of their theories : a constant and perfect agreement with the 
phenomena, as far as can be discovered. 
The great criterion in the present case is, whether on the 
conversion of a substance into its several compounds, and of 
these into one another, the simple ratios always obtain which 
the principles of the theory require. Amongst the multitude 
of instances which I could adduce, in support of such being 
the fact, I will, for the sake of brevity, confine myself to a 
few in the substances which have come under consideration 
above, as they will likewise give the grounds on which some 
of the proportions in the table have been assigned, and every 
chemist, by a careful repetition of the experiments, may easily 
determine for himself to what attention the present theory is 
entitled. 
Lead - - = i. of sulphate of lead 
= f of sulphuret of lead 
Sulphuret of lead = of lead 
= of sulphate of lead 
Sulphate of lead — of lead 
= £ of sulphuret of lead 
Antimony - = of powder of algoroth 
== J of sulphuret of antimony 
Sulphuret of anti- 
mony - = “ of powder of algoroth. 
In the experiments by which these relations were ascer- 
tained, the portion of powder of algoroth and sulphate of lead 
I 2 
