Letter – Nicholas Walton to Peter Mulcaster – 30 Sep 1770

Mr Mulcaster. 							Farnacres 30th September 1770



      Since I received your Letter inclosing the three last Assays, I have often thought about the Litharge taken from the Silver Test, and am in some doubt whether putting the Litharge into a Test again, before it is Reduced into Lead, is so proper as to reduce it first; so as the Litharge Swims upon the Surface of the Melted Lead in the Test, the Rich Litharge may be blown off at the Gate before it leaves the Silver, this would undoubtedly in a great measure, if not wholy, be prevented by Reducing the Rich Litharge into Lead before it is put into a Test again; and I should think in all cases where the Tests are observed to run Lead (which I have understood it requires judgement and a constant attention to prevent) that the Flats of Litharge ought to be laid by themselves, and Reduced to Lead before an attempt is made to come at the Silver in them. I think the Silver which comes off with the Litharge, when the Test does not run Lead, is itself converted into Litharge, if that is a fact, or if it is in such small Particles as to be Suspended by the Litharge of the Lead, you will consider with yourself, whether it may not continue so after being put into the Test in the State of Litharge, if it does, it must unavoidably come off without leaving the Silver behind. Upon the whole I must observe that it seems to me proper to consider those matters very well and to Refine such Lead as comes from Rich Litharge in the Silver Test. I am sure you will give the above all due attention and am

      Your most Hble Servt

      NW Junr