7 May 1844
I sent this morng to Mr Palmers <2> but he was not in but my Clk purchased the Book herewith sent & the Iodized paper & yr infn is therefore correct – The sale of the paper is I apprehend an infringt of yr patent & that it will be proper to give notice to the Parties which I will attend to when I receive yr instrons on the subject.
2. Edward Palmer, Chemical and Philosophical Instrument Maker, of 103 Newgate St, London, began selling photogenic paper, fixing liquids and portable field cameras in 1839; see, for example, his advertisement in The Athenæum, no. 603, 18 May 1839, p. 361. These supplies were based on WHFT’s freely-published formulas, although he was not credited by Palmer. By the 1843 Post Office Directory, Palmer had expanded his specialties to include “optician, mathematician, chemical & philosophical instrument maker, & electrotypist”. The iodized paper was part of WHFT’s patented calotype process.