LIVERPOOL CHEMISTS’ ASSOCIATION. 
625 
it is the work of our hands and the conception of our intelligence ? and this result can 
be consummated by any painstaking chemist possessing a small share of the inspiration 
of an artist. Leaving out the art-question altogether, we still have something which 
brings with it, hut in a much higher degree, the pleasurable sensation of the young 
chemist to whom I have already alluded. 
Photography, although a child of the present generation, has effected much for science 
in optical knowledge, but more especially in chemistry. It has brought to light many 
reactions which before were never dreamt of. It has led to the investigation of a class 
of salts and compounds which before its introduction were very obscure, because they 
were considered unimportant. It has interested a class of men in the study of chemistry 
who before time looked upon it as a very dry subject, picturing its votaries as men, de¬ 
scribed by the poets and novelists, in slippers and dressing-gowns, burning the midnight 
oil, and poring over the molten contents of the crucible. Happily, however, this enthrall¬ 
ing study has dispelled many of these visions of fancy, and there are now to be numbered 
among photographers men who once thought lightly on scientific matters, but now are 
to be found among their most enthusiastic admirers. This change may be solely attri¬ 
buted to the influence of the photographic art, which first brought these subjects under 
their notice in so enchanting a disguise. 
It may not perhaps be out of place here to glance at one or two of the leading ques- 
. tions in this branch of chemical research, which are now engaging the attention of the 
learned. It will appear somewhat strange to the uninitiated that the very foundation 
of all photography is not yet acknowledged to be clearly understood. The formation of 
the “ photographic image” (the subject to which I allude) has received a considerable 
share of attention by chemists ; but the changes which take place are of such a subtle 
nature,—nay, the very action of light itself on the sensitive tablet has been hitherto 
wrapt in such obscurity, and besides these, there is the undoubted combined influence 
of electricity, the whole being so intimately woven that the chemist alone becomes 
powerless to grapple with the question, and has to call in the aid of the philosopher to 
assist him in the unravelment of the skein of mystery. In the course of the year that 
has passed, I attempted a few efforts in this direction, and I trust not altogether in 
vain. At some future time I shall have pleasure in laying before this Association the 
result of my experiments, if it is thought that the members will take any interest in a 
subject at present so foreign in its nature to the general routine of its business. 
Out of the many other questions which are now receiving the investigation of scien¬ 
tific photographers I will mention but one more, and that because it is of the utmost 
importance, affecting the great matter of the imperishability of the final results. The 
process of printing upon paper by means of the action of light on chloride of silver has 
for some years been a stumbling-block and root of bitterness to the followers of the art. 
The question becomes more and more complicated by the fact, which is constantly 
brought before us, that while some of those pictures which were produced during the 
infancy of the process have withstood the ravages of time and retain their pristine 
beauty, although frequently very little care has been bestowed upon their preservation, 
there are others which, as far as human intelligence can judge, have been treated identi¬ 
cally the same, which are but of yesterday comparatively speaking, but are fading from 
our view, leaving scarce “ a wreck behind.” 
Efforts are now being put forth to produce the positive images by other means than 
that of silver printing, and, I am happy to add, with marked success. Not the least 
important is the attempt to substitute carbon for the silver, which has only very recently 
been satisfactorily accomplished by Mr. Swan, of Newcastle-on-Tyne. The details of 
his process have just been published in a paper read this month at a meeting of the 
London Photographic Society, and I have the pleasure to lay before you one of the 
specimens. The results are acknowledged by all to be equal, if not superior to silver 
prints, and there can be no doubt with regard to their permanency. * 
Perhaps the greatest novelty, and the one which will outvie all others for popular 
illustration by means of photography, is the transfer of the photograph itself to the 
copper-plate and the lithographic stone. There now exists not the least doubt but that 
this feat will be satisfactorily accomplished. 
In appearing before you this evening as a body devoted expressly to the world of 
chemistry, I have a specific object in view. If any branch of art or science is worth 
following at all, it is desirable that it should be pursued in a systematic manner. I 
