Re: archivalness of gum

[Judy Seigel <jseigel@panix.com>]

On Sat, 22 Dec 2007, Christina Z. Anderson wrote:

> P.S. I wanted to also add, Judy, that my stain test chapter is now organized 
> into sections--stain tests WITH exposure and stain tests WITHOUT exposure 
> (can I possibly be any more obsessive compulsive???!!). In chronological 
> order, heheheheheh. 2 11pt. single spaced pages of different stain tests 
> WITHOUT exposure, and one bitty paragraph devoted to you and a guy named 
> Richards from 1905.
>
> Richards back in the dawn of time stated that he does not find it enough to 
> just coat the paper and dry and wash to do this test, but to give a bit of 
> exposure, because he finds that the pigment will not leave the paper 
> sometimes unless it has had a little light action.  "This will be noticed now 
> and then in a print which will develop into a picture with the high lights 
> pure and white, whilst the edges of the print which have been protected from 
> light by the rebate of the frame still retain a considerable amount of 
> pigment."
The effect may be related to Mike Ware's theory, maybe 95 years later -- 
as I've quoted many times :  that the bit of exposure makes the emulsion 
more viscous, hence more likely to clear (or words to -- roughly -- that 
effect).

> He developed the bend test:  "coat a strip of the paper with the 
> sensitized pigment solution.  After dry, bend it in a zigzag.  Expose to 
> light a minute or so and put in water.  See that in the bends where no 
> exposure occurred if after 10 mn the pigment has left the paper-if so, 
> it is suitable."
> So he is still reading from the no exposure parts which is also funny!
Delicious....I think some of these folks didn't have enough to do (no TV, 
no internet, and womenfolk cleaning up after them).  But it also seems to 
me they're overlooking the main factor controlling stain IN MY STUDIO: 
NYC Heat times Humidity.

> > > And, Judy, as an aside, I have a nice little chapter on the dreaded stain 
> > > test, tracing its origins, who brought it from Germany to England and then 
> > > to America.  Word for word..culprit for culprit. I'm dedicating that 
> > > chapter to you :)  There was the distinct feel that the Germans were more 
> > > scientific about gum and hence "modern" or "better". But we postmodernists 
> > > know better than to be scientific about gum, heheheheheh.
Have you got the part where Demachy says "les etrangeres" ("foreigners," 
meaning primarily the Austrians/Germans do multiple coats but he (and 
Puyo, among the French) do only one coat?

But this is all too interesting -- do you know how much reality I've got 
waiting, piled up in my hair (to mix metaphors)?

J.