PHOTOGRAPHY APPLIED TO TERRA-COTTA AND OPAL GLASS.

In the natural course of things it must necessarily have occurred to

practical men to utilize photography in the case of terra-cotta, as it

has already been employed in connection with so many other wares; but I

have not to this day known of its successful application to terra-cotta.

Now this is strange, if one considers how fashionable _plaque_ and plate

painting have become of late, and the good photographic results that

are easily obtained on these as on sundry articles of this same "burnt

earth." Portraits, animals, landscapes, seascapes, and reproductions are

one and all easily transferred, whether for painting upon or to be left

purely photographic. As a matter of business, too, one fails to see

that it would not be remunerative, but rather the contrary. It was with

something of this feeling that I was led to try and see what could be

done to attain the end in view, and as I knew of no data to go by, I had

to use my own experience, or rather experiment on my own account.

Since emulsion was constantly at hand in my establishment, in the

commercial production of my gelatine dry plates, it was but natural I

should first have turned to this as a mode of obtaining the desired

results; but, alas! all attempts in that direction signally failed--the

ware most persistently refused to have anything to do with emulsion. The

bugbear was the fixing agent or hypo., which not only left indelible

marks, but, despite any amount of washing, the image on a finished plate

vanished to nothing at the end of an hour's exposure in the show window.

There was nothing left but to seek other means for the attainment of my

object. I would not have troubled the reader as to this unsuccessful

line of experiment but that I wished to put him on his guard and save

him useless researches in the same direction. To cut matters short, the

method I found best and most direct was the now old but still excellent

wet collodion transfer. I will now proceed to detail my system of

working to facilitate the matter to the inexperienced in collodion

transfer.

Scientific American Supplement, No. 401, September 8, 1883 · 第 7 / 67 题