Faraday to Peter Henry Berthon   7 February 1859

Royal Institution | 7 February 1859

Sir

I have carefully analyzed & examined the four samples of Red lead labled as under | 1 | 2 | 3 | 4¹

I do not find in any of them any impurity or adulteration; or substance added to make weight. In that respect they are all alike & unobjectionable. There are I believe variations in quality dependant upon the mode of manufacture & the care taken in the operation but on these points I do not profess to be a judge[.] As far as I can see they are well manufactured articles²[.]

I am Sir | Your faithful Servant | M. Faraday

P.H. Berthon Esqr | &c &c &c