r plain nitrate) and fixed by
plain hyposulphite without any coloring bath. * * * I have tried the
hyposulphite of gold on some of the silver-developed prints prepared with
the hydrofluate of the uranic oxide and fixed with ammonia, which had an
exceedingly unpleasant raw-red color, a very agreeable gray was at once
obtained. I have succeeded in getting very beautiful impressions by
development of the uranic paper by chloride of gold alone."

In another communication to the _Photographic Notes_, more interesting
perhaps than the foregoing, Mr. Burnett says:

"The clearest and brightest of my results have been obtained by the action
of gallic acid, tannin, or especially a _mixture of tannin and carbonate
of ammonia_, potash or soda, on the blue pictures obtained by the
solarization of paper prepared with ferridcyanide of potassium,
ferrocyanide or ferridcyanide of ammonium. * * * I have also experimented
with the bichromate and iron, with gallic, tannin and other developer; but
I must confess to not having been, in this particular way, so successful
as Mr. Sella appears to have been in the preservation of the whites, owing
possibly to my not having taken the trouble to wash out sufficiently the
iron before toning."(1)

"I have experimented most extensively in many ways with the chromates and
bichromates, and have succeeded in various ways in getting _very good_
results. A very capital process for many purposes is to float or steep
your paper in a mixed solution of bichromate of potash and sulphate of
copper. As for E. Hunt's chromotype process," (2) I have mixed gelatine,
or occasionally grape sugar, or both, with the solution, but instead of
developing it by a silver solution, as in the chromotype, wash out the
salts unacted on by light, and develop by floating on a solution of
ferrocyanide of potassium. The color of the red copper salt which now
forms the picture may be modified or changed in many ways, viz., by
soaking the picture, after the ferrocyanide of potassium has been washed
out of the lights, in a solution of sulphate of iron (or the iron salt
may, but not so advantageously, have been applied to the picture before
the application of the ferrocyanide). Solutions of chloride of tin,
gallic and tannic acids, alone or with alkalies or alkaline carbonates,
may also be employed to modify or change the color. Instead of developing
by ferrocyanide you may develop by the cobalt or chromo-cyanogen salts, or
by