Mineral Point tribune. (Mineral Point, Wis.) 1869-1938, 1878-12-25

utaut 10 appear In various
colors. The use OF such means for
secret correspondence is very ancient.
OVID. Pllny and other Roman writer's
speak of an ink of this kind, which,
however, was nothing more than fresh
mllk. 1t merely suiiiced to dust DOW
dered charcoal over the surface of the
paper upon which characters had been
traced with the coloiess fluid, when the
black powder adhered only 20 those
places where the fatty matter of the
milk had spread. Such process, how
ever, was merely mechanical, and the
results very crude.
"A great number of sympathetic inks
may be obtained by means of reactions
known to chemistry. For instance,
write on paper with coloress solution
# sugar of lead; if the water that is
used for the solution be pure, no trace
of the writing will remain when it be-
comes dry. Now hold the paper over a
Jet of sulphureted hydrogen, and the
characters will Immediately appear on
the paper, OF an intense black color.
Inc following recipes for inks of this
KIND are more simple; If writing be
executed with dilute solution of sui
phate of iron, The invisible characters
Will appear of IL beautiful blue if the
dry paper be brushed over with n pen
cll full OF II solution of yellow prussiatc
of potash; or they will be black, if a
solution oftannin be substituted for the
prussiate. II the characters be written
with solution Of sulphate of copper,
they will at once turn blue on exposure
to the yapors of ammonia. Another
sympathetic ink is afforded by chlo-
ride of gold, which becomes reddish
purple when acted upon by salt of
TN. A red sympathetic ink may be
made IN the following manner: Write
with a very dilute solution of perchlo-
ride of iron--so dilute, indeed, that the
writing will be invisible when dry. 3y
holding the paper in the vapor arising
from long-necked glass flask contain
ing sulphuric acid and few drops of
a solution of sui pho-cyanide of potas-
SUM, the characters will appear Of n
blood-red color, which will again disap-
pear on submitting them to the vapors
OF caustc ammonia. This experiment
can be repeated ad intinitum.
Daring the war in India some wears
ago, important correspondence was car
ried on by the English by means of the
use OF rice water rs n writing fluid. On
the application Of iodine the dispatches
Immediately appeared in blue charac-
tiers.
Sympathetic inks which are devel-
oped under the influence of heat only
are much easier to use than the iorego-
ing. The liquids which possess such a
property are very numerous. Almost
every one, perhaps, knows that if writ
ing be executed on paper with clean
quill pen dipped in onion or turnip
juice, 1t becomes absolutely invisible
when dry; and that when the paprr is
heated the writing at once makes its
appearance in characters Of brown
color. All albuminoid, muciIagiou,
and saccharine vegetable juices make
excellent sympathetic inks; we may
cite, as among the best, the juices OF
lemon, orange, apple and pear. A di-
lutte solution of chloride of copper used
for writing is invisible until the paper is
heated, when, the letters are seen of II
beautiful yellow, disappearing again
when the heat that developed them is
removed. The salts Of cobalt, AZ the
acetate, nitrate, sul plate and chloride,
possess like properly. When II dilute
solution Of these salts is used as an
ink, the writing, although invisible
when dry, becomes blue when exposed
to heat The addition Of chloride of
iron, or Of salt Of nickel, renders them
green, and this opens the way for n
very pretty experiment: If winter
landscape be drawn III India ink, and
the sky be painted with " wash of
cobalt alone, and the branches Of the
trees be clothed with leaves executed
with a mixture of cobalt and nickel,
and the snow-clad earth be washed over
with the same mixture, n magic trans
formation at once takes place I'm the
of heat, the winter land
scape changing TO summer scene.
" There is well-knoNn proprietary
article sold in Paris under the name Of
Encre pour les Danes link for ladies J
Hager, in n recent scientific journal,
states that this consists OF an equOus
solution Of iodide Of starch, and is
specially intended for love letters. In
four weeks characters written with it
disappear, preventing all abuse OF let
tiers, and doing away with all docum en-
tary evidence Of any kind in the hand
OF the recipient. The signers Of bills Of
exchange who use this ink are OF course
freed from all Obligations in the same
length of time"
Woman may revere man powers,
his intelligence, and, mayhap, his super
iority; but when he comes to taking up
a pan OF ashes, she covers up every