Judy Seigel (jseigel@panix.com)
Mon, 22 Mar 1999 15:40:44 -0500 (EST)
On Mon, 22 Mar 1999, Richard Sullivan wrote:
> At 10:47 PM 3/21/99 -0500, Judy wrote:
> >I never had the patience to mix all the chemicals you needed with the
> >Rochelle-salt developers, they really took huge amounts, at least the
> >formulas I had. In fact I couldn't get them all into solution & then they
> >didn't last very long.
>
>
> I believe the old formulas called for sodium borate decahydrate which has a
> molecular weight of 381.37 where the (dry) fused version has a molecular
> weight of 201.22. None of the historical formulas specify which hydrate to
> use but I strongly suspect that it is the decahydrate. I think most people
> will end up today with the dry version. Thus if the old formula calls for
> 500 grams you would use only 260 gms of the dry stuff. This accounts for
> why you have all that sludge in your tray when you try to mix the old
> formulas.
As noted, I was using "Rochelle Salts" (+ Borax), bought by that name, tho
listed as "Potassium and Sodium Tartrate" in Cassell's. In any event, no
sludge, just too much cost & mixing. Even half as much was too much.
As for silver nitrate in kallitype *developer*, I have 20, 30, maybe more,
old formulas, articles, etc. on kallitype. None mentions that (although I
have seen one contemporary formula with it). Are you sure you didn't
confuse with salted paper?
Judy
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