Re: Autoclaving gum and gelatin

> Judy Seigel wrote:
>>
>> Tracing the print history back, there was (in the case of speckles) just
>> about every time, the finding that they had developed the print by hosing
>> with scalding water or overheated the gelatin in melting it, or some other
>> excess application of heat.

On Sun, 6 Feb 2005, Sandy King wrote:

> You are throwing a lot of possibilities in the mix. Before jumping to
> conclusions as to the cause I would recommend that you test it yourself.

Test what? My students weren't morons. If they said they'd scalded the
print with the hose from the sink (where the water mysteriously turned
scalding at 11 AM Monday mornings -- really!), I believe it. If you
don't... that's not my problem.

> Without knowing how hot the students allowed the gelatin to get, or how long
> they held it at that temperature, conclusions as to the cause of speckles
> seem pretty speculative to me.

The best term I can come up with for this is pettifogging !!!

I am only "throwing" the probability of the gelatin being scalded or
overheated into "the mix" when characteristic speckling of a particular
type appeared in those circumstances and NO OTHER that I saw. I was trying
to be helpful to Mr. Autoclave -- I'm not trying for a Nobel prize. In my
teaching experience, any time this characteristic speckling appeared there
was either scalding or overcooking OF THE GELATIN in the operation.

Other than that (and the occasional inattentive student who dried the gum
emulsion with a hairdryer on hot, so the emulsion cooked & didn't develop)
the gum printing medium, which is supposed to be so tricky, fraught, and
difficult, went quite nicely -- especially given that much of this was in
the early years when the guys especially thought gum printing was for
faggots & just wanted to be in their darkrooms making C prints. They
often, even usually, got to like it, too.

[Note: If anyone wants to tut tut about the word faggot -- be my guest. I
live in faggot city and have special dispensation to use the term from my
dearest faggots, who use it too.]

I suppose I should be flattered that the Gotcha Gang comes after me on
this point. Rather than tell the would-be autoclaver that that might not
be a good idea, they're stretching, inventing, doubting, cavilling,
nitpicking, qualifying, supposing, stonewalling, as I say above,
pettifogging, and generally remixing the nature of gelatin in hopes of
proving me wrong.

Sandy: What else do you suppose by miraculous coincidence caused
speckling in just those prints where the gelatin had in some way been
scalded and never in others? (That's a rhetorical question. I expect
you'll come up with something -- though see below for another possiblity.)

Christina: (a) You say "if Jello starts with boiling water," etc. How did
you come up with that? Is that on the package now? What I wrote was that
Jello packages used to say "dissolve in hot, NOT boiling water." If you
changed that to "starts with boiling water," how can I believe another
thing you say? If today's packages do say start with boiling water, as I
suppose is possible (what is the world coming to?), I note that there are
other ingredients in the package (as there are in, for instance, chiffon
pie); Jello is in fact largely sugar and flavoring, which would change the
equation. We did not add eiter sugar or flavoring to our sizing gelatin.

Christina: (b) For the first 10 or so years we were using formaldehyde,
so our lungs got speckled (and our eyes and noses -- imagine 30
undergraduates formaldehyding -- even outdoors, as we did). Thus your
theory that the speckling was due to the glyoxal is another stretch, as
you, too, desperately seek ANY other explanation.

That's not even to mention that I never have found any such "speckling"
attributable to either formaldehyde *or* glyoxal. Which is not to say you
didn't, but that our experience with glyoxal (which I have used on maybe 6
or 8 papers over the years, the students on probably a wider variety, but
beginning each semester with Rives BFK) was that it was great. The only
trouble was that the working solution didn't keep, and IN SOME CASES the
paper yellowed if not used promptly.

Ryuji: I taught the class for 14 years with usually 30 (or more) students
(in 2 classes) per semester. If each student made a minimum of 6 gum
prints (many made more), that's at least 2,520 prints, of which the
speckling appeared possibly a dozen times. If this isn't convincing, I
have only two explanations:

1. This company is, for reasons of its own, heavily invested in finding me
wrong. Nothing will convince them, and as of this e-mail I will stop
wasting my energy trying. The only qualification I think worth adding is
that the 140 degrees was usually an estimate. We rarely heated the gelatin
with a thermometer. We heated until it was too hot to keep a finger in it.
Then it went into a tray which sat in a larger tray of hot water. If the
room was chilly it might still get too cool before we finished and went
back into the pot to reheat with stirring, subject to the finger test.

2. However, one other possibility should be considered: My class was
haunted by the Speckle Fairy, leading us all astray in advance for the
purposes of this list.

Finally, Sandy says:

> I have done some gum printing also and it does appear to me that the
> function, which appears to be the ability of the gelatin to change states is
> indeed the primary function for gum as well as carbon. I could be wrong about

I don't understand what you mean by "the function, which appears to be the
ability of gelatin to change states." EVERYTHING changes states. Milk
changes states when you boil it, or when you add lemon juice, upon which
it curdles and/or turns into cottage cheese... Meat changes states when
you cook it...etc. I'm changing states too -- to a state of exasperation
(or Connecticut).

> this of course, but for the time being I am going to continue to believe I am
> right.
>
> Sandy

I daresay you will...

Judy
Received on Sun Feb 6 21:25:00 2005