Jany 11 – 1843
I received your favour of the 9th inst <1> and must beg you to pardon me for having committed so great a practical blunder as to have asked a Patentee gratuitously to communicate the method of his patented invention <2> – but I was quite ignorant of the Patent having been taken out or I should not have, in the first place, endeavoured to infringe it, which it seems I have been doing, or in the next place have made the request contained in my last, for which I sincerely beg pardon, I trust you will accept the above as my excuse
I am Sir Your obt Servt
John Dickinson Brunton
2. This was WHFT's patent for the calotype process, "Improvements in Obtaining Pictures or Representations of Objects," no. 8842. Brunton was probably truly sympathetic to WHFT's position, for he held patents himself, and later in life was to be involved in controversies over their infringement.