vids, of
Rutherford, New Jersey, sends the following formula, which he
recommends very highly. We shall publish in our papers for
beginners several formulas for developing solutions, with prices
of chemicals.

_Hydroquinon Developer._--Sodium sulphite, 460 grains; sodium
carbonate, 960 grains; hydroquinon, 96 grains; water, 16 ounces.

1. Mix and filter before using. In No. 786 will be found a simple
developer for instantaneous pictures. 2. Directions for preparing
sensitive paper will be found in Nos. 786 and 803. 3. Directions
for polishing ferrotype plates will be found in Nos. 797 and 805.
4. A ruby light for dark-room work may be made by taking a wooden
starch-box, cutting a square hole in the cover, and pasting two
thicknesses of red fabric over the opening. A hole must be made in
one end of the box--which answers for the top of the lantern--to
allow for ventilation. This must be shielded so as to prevent the
escape of actinic rays. This may be done by pieces of tin bent so
that air can enter, but no white light escape. A candle should be
used with this style of lantern. 5. Ammonia in its pure state is a
gas which combines readily with water, water taking up of the gas
five hundred times its own volume. This is liquid ammonia, or
stronger water of ammonia. By diluting it with water it becomes
the spirits of hartshorn, or ammonia water. 6. Bromide of ammonia
is formed in the simplest manner by the addition of bromine to
water of ammonia. It is very useful in photographic work. It gives
great sensitiveness to gelatine and collodion emulsions--combined
with pyro for a developer it prevents fog--and is employed in the
preparation of sensitive papers.

[Illustration: THE PUDDING STICK]

This Department is conducted in the interest of Girls and Young
Women, and the Editor will be pleased to answer any question on
the subject so far as possible. Correspondents should address
Editor.

Lillie M---- came to see me yesterday, and after she had gone, Maria
G----, who was putting a new braid on my second-best gown, said:

"That Miss Lillie uses very nice perfumery. It's so faint and fine, not
anything you can smell a long way off, but something which makes you
think of roses or violets when she passes you on the street. How does
she manage it?"

Maria G----