Slough
April 19/40

My dear Sir

I have just rec^d the enclosed specimens from M^r Hunt ^<1> a chemist at Devonport who has been working very successfully at the Photographic processes using papers initially black which light whitens. They appear to me to promise so well that I could not resist sending them – and also to enquire whether you have duly received the revises which I directed to be sent you of my paper ^<2> the printing of which is now finished and as soon as the engraving can be done a copy will be sent you in its complete state.

I remain My dear Sir Yours very truly
JFW Herschel

Turn over

Of all this superb weather I have been able to make not a slightest use! Every thing I have in the way of apparatus is packed and on its way to Hawkhurst where henceforward please to address me should you have occasion to write or reply to this.

Sir J. H.
Collingwood
Hawkhurst
Kent

H. F. Talbot Esq^r
Lacock Abbey
Chippenham
Wilts

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Notes:

1. Robert Hunt (1807–1887), scientist & photographic historian.

2. John Frederick William Herschel, ‘On the Chemical Action of the Rays of the Solar Spectrum on Preparations of Silver and Other Substances, Both Metallic and Non-metallic, and on Some Photographic Processes,’ Philosophical Transactions of the Royal Society of London, 1840, pp. 1–59.