Well, actually, I was more or less asleep, isn't everybody? I mean
it's usually late at night & I'm trying to get something done, for once.
And, nature being relentless, I fall asleep... doesn't everybody?
BUT,in this case I might well have asked the question awake -- it came
from Carmen who grabbed me while I was riding herd on 16 undergraduates --
like giving a birthday party for 10-year olds -- and asked for
formaldehyde, which I didn't have & then "alum" which I do have, but
neither of us knew which one. Heedlessly, I said I'd "ask the list,"
little realizing what ignominy I was about to suffer. But, since I am
downloading all these messages into a carbon printing "tech pack" she'll
see how bad we both have been and I am sure will be as contrite as
possible, which of course I am too.
I haven't a clue, BTW, what she planned to harden -- it's probably Klaus's
fault, since I *think* she's following his instructions. Or maybe KoL.
Meanwhile, we were gelatine-sizing paper for gum and hardening in glyoxal
(which maybe is OK for whatever she wanted it for), and another student
asked why we don't use alum instead of glyoxal for paper sizing. I said
the claim has been made (or so I have read) that alum can deteriorate
pigment or paper. But I surely would appreciate comments from you or Sil,
or any other alum mavens in the vicinity about that...
Meanwhile, there may be some clue in Sil's (clear concise comprehensive,
thank you) rundown on alums, about the potassium aluminum sulfate being
acidic .... it's my understanding that low pH slows action in gum
printing...... plus the possibility of course of bad effects on the paper
from the acid.
Wakefully (it's only 11:15 PM),
Judy