what Demachy said....
When someone asked me a question about gum printing recently, I said one of the reasons I put it in Post-Factory (especially Issue #1) was so I wouldn't have to remember everything/anything off the top of my head.... But then I figured I ought to check -- I hadn't looked at #1 (not the inside) in several years.
As it happened, versions of the current gum discussion were absorbing the list at the time (& I'm not knocking them -- information does come out, besides all the fun). Still, I was enchanted to come upon the following, which I'd totally forgotten:
Page 4, titled "Painter-Photographer/Photographer-Painter," starts with an excerpt from Demachy: He'd been at his photo store, he said, complaining to the dealer that he couldn't get a good black with gelatino-bromide paper, when another customer asked, "Why don't you try Poitevin's gum process... you just mix together some gum arabic, some bichromate of potash, and a small quantity of moist water-color pigment. You coat any sort of drawing paper, print, & develop with cold or tepid water." Demachy said he bought the ingredients "there & then," and "after a week or so of experiment got 'a few fair results which were exhibited at the London Photographic Salon.'"
HOWEVER, ten years later he had a different perspective: "If, instead of meeting my concise and unknown friend, I had read one or two papers of the same order as most of the modern treatises on gum, I would have fled, appalled by the tremendous intricacies of the process."
PS. The rest of P-F #1, including more Demachy, is on alternativephotography.com. (Plus all those galleries -- wow!)