post sensitizing coated gum paper

Someone a while back (Martin?) was questioning whether you could float a
coated gum paper on a dichromate bath to sensitize as you can carbon. I
finally came across the reference to this last night (actually, a number of
them) in the BJP aside from the Wall mention I think I posted.

For what it is worth (historically, now!) a guy named J Page Croft sold gum
paper, both sensitized and unsensitized. The sensitized lasted for a month
if "kept under pressure" whatever he means by that. The unsensitized had
the addition of "methylated spirit and sulphuric acid to harden the coating
for the immersion in bichromate."

Otherwise, there were papers that had some combinations of fish glue, syrup,
sugar, gelatin, albumen, etc. etc. in them that were commercially sold, one
being, of course, Artigue. Artigue paper--lots and lots on this, and people
were always trying to figure out the ingredients therein that made it such a
luscious paper.

My morning history lesson. Only 48 more BJP articles left to read...but
fascinating stuff.
Chris
Received on Fri Jun 18 08:34:15 2004