The following formulae are taken from a book published in 1903, I'm
transcibing as they are, together with the metric equivalents, you had
better check the latter as my arithmetic ain't what it used to be!
Rapid Sensitiser.
Ferric Ammonium Citrate (Green) 110 grains 7.1 gm
Uranium Nitrate * 30 grains 2.37 gm
Water 1 oz 28.4 ml
Print to a faint image and develope in 5% potassiun ferricyanide
* This should make the print glow in the dark, and with the end of the
cold war it should also be quite plentiful!!
Greenish Black Toner
Borax 30 grains 1.95 gm
Water 1 oz 28.4 ml
Acidify with sulphuric acid until soln just reddens litmus, then add 10%
ammonia until colour just changes.
Add:-
Catechu ?* 4 grains 0.26 gm
Shake well and filter. Tone the washed print in this soln.
Wot's this? I've checked in various upto date chemistry books (1896).No
joy!
Another one for the wizz kids at Aldrich perhaps Terry?
Brown to Black Tones.
Place dry print in Ammonia soln. 6 minims per oz (approx 6.3 ml per
500ml).
When bleached rinse and place print in Tannic acid soln 9 grains per oz.
(0.58 gm per 28.4 ml)
Black tones (Lagranges Process).
Bleach in Silver Nitrate 9 grains per oz (0.58 gm per 28.4 ml)
Wash well, fume with Ammonia and expose to light. then develope in
Ferrous Oxalate*.
No details given for this, but perhaps:-
1 part ferrous sulphate 25% added to three parts of neutral Potassium
Oxalate 25%, with constant stirring might be worth trying.
Lilac Tones. (Affected by light and damp!)
Soak print in in a 35% soln of Potassium Sulphocyanide( Potassium
Thiocyanate?), containing a little Lead Acetate.
That's All Folks! I hope that the formulae will be of interest. Even if
they don't work they do go to show what fun our ancestors had!
Alex.
Alex Nanson
Gloucester UK