"It is obvious that, in the process so conducted by me with the solar microscope, I was virtually _within_ my camera, standing between the object and the prepared paper. Hence the exciting and developing processes were conducted under _one operation_ (subsequently patented by Talbot), and the fact of a latent image being brought out was not forced upon my attention. I did, however, perceive this phenomenon upon one occasion, after I had been suddenly called away, when taking an impression of the _Trientalis Europæa_--and surprised enough I was, and stood in astonishment to look at it. But with all this, I was only, as the judge said, "_very hot_." I did not realize the _master fact_ that the latent image which had been developed was the basis of photographic manipulation. The merit of this discovery is Talbot's, and his only, and I honour him greatly for his skill and earlier discernment. I was, indeed, myself fully aware that the image darkened under the influence of my sensitiser, while I placed my hand before the lens of the instrument to stop out the light; and my solar mezzotint, as I then termed it, was, in fact, brought out and perfected under my own eye by the agency of gallic acid in the infusion, rather than by the influence of direct solar action. But the notion of developing a latent image in these microscopic photographs never crossed my mind, even after I had witnessed such development in the _Trientalis Europæa_. My original notion was that the infusion of galls, added to the wet chloride or nitrate paper while the picture was thrown upon it, produced only a new and highly sensitive compound; whereas, by its peculiar and continuous action after the first impact of light on the now sensitive paper, I was also, as Talbot has shown, employing its property of development as well as excitement. My ignorance of its properties was no bar to its action. However, I threw the _ball_, and Talbot caught it, and no man can be more willing than myself to acknowledge our obligations to this distinguished photographer. He compelled the world to listen to him, and he had something worth hearing to communicate; and it is a sufficient return to me that he publicly acknowledged his obligation to me, with reference to what Sir David Brewster calls 'an essential part of his patent' (_vide North British Review_, No. 14 article--'Photography').