From: Judy Seigel (jseigel@panix.com)
Date: 12/10/01-10:05:09 PM Z
On Mon, 10 Dec 2001, Sandy King wrote:
> Judy Seigel wrote:
>>
> >He also says the potassium (colorless) alum keeps its hardening properties
> >much better than chrome alum in solution, but gives no criteria for time
> >or hardening properties in either entry.... which you do below. Thank you.
> >Did you figure that out yourself or read it somewhere? If the latter,
> >where?
>
> Many of the older resource books on carbon recommend the use of
> chrome alum for single transfer supports and potassium alum for
> double transfer. I don't remember if any of these books actually says
> that chrome alum hardens better than potassium alum but if one
> actually works with the process in both ways this becomes immediately
> apparent through the surface qualities of the papers one works with.
>
I was pointing to the fact that he changes terms midstream. That is, under
the chrome alum he refers to white alum, presumably the potassium alum,
but under potassium alum he never says "this is the white alum", only
referring to it as "common" or colorless, so that a person could well
think there was some THIRD kind of alum, not in the index.
This kind of thing does happen, but not good manual writing.
J.
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