[This application is not a novelty to us: DR. DIAMOND has for some time
added a small portion of his amber varnish (which is prepared from
chloroform) to his collodion, and with satisfactory results. It is a
pity that so admirable a varnish is not to be procured at the
generality of photographic warehouses. We have never yet been able to
procure any which will bear comparison with some which DR. DIAMOND was
good enough to prepare for us.--ED. "N. & Q."]
_Printing Positives._--I will venture to assure AMATEUR that,--if he will
follow DR. DIAMOND'S formula for albumenizing Canson paper, either positive
or negative, viz.,
Chloride of sodium (salt) 5 grs.
Chloride of ammonium 5 grs.
Water 1 oz.
Albumen, or the white of one egg, which
is near enough for the purpose 1 oz.
and will excite this paper by floating it for about two minutes on a
solution of nitrate of silver twenty grains to the ounce, distilled
water,--provided his chemicals are good, he will obtain perfectly
satisfactory results.
Let his fixing bath be a saturated solution of hypo. soda, and if newly
made let him, as recommended by DR. DIAMOND, add 40 grains of chloride of
silver to every 8 ounces of the solution. The addition of a grain of sel
d'or to every 8 ounces of solution will greatly improve the tones of
colour; and if, after some {407} time, the positives become more of a brown
tint than he likes, let him add a small quantity of sel d'or, half a grain
to a bath of from 12 to 16 ounces, and he will find the dark tints
restored.
I inclose a copy of the print of "Horse-shoeing," obtained precisely by the
method described. It is rather overprinted; but if AMATEUR will give you
his address, and you will forward it to him, it will show him what tones of
colour and depth may be procured by following the foregoing directions.