of the speculum, and lay the speculum face down in one of the
dishes; fill the dish with distilled water, and clean the face of
the speculum with nitric acid, until the water will stick to it in
an unbroken film.

The recipe for silvering the speculum is:

Solution A:
Distilled water.............................4 oz.
Silver nitrate............................100 gr.

Solution B:
Distilled water.............................4 oz.
Caustic stick potash (pure by alcohol)....100 gr.

Solution C:
Aqua Ammonia.

Solution D:
Sugar loaf................................840 gr.
Nitric acid................................39 gr.
Alcohol (Pure).............................25 gr.

Mix solution D and make up to 25 fluid oz. with distilled water,
pour into a bottle and carefully put away in a safe place for
future use, as it works better when old:

Now take solution A and set aside in a small bottle one-tenth of
it, and pour the rest into the empty dish; add the ammonia
solution drop by drop; a dark brown precipitate will form and
subside; stop adding ammonia solution as soon as the bath clears.
Then add solution B, then ammonia until bath is clear. Now add
enough of the solution A, that was set aside, to bring the bath to
a warm saffron color without destroying its transparency. Then add
1 oz. of solution D and stir until bath grows dark. Place the
speculum, face down, in the bath and leave until the silver rises,
then raise the speculum and rinse with distilled water. The small
flat mirror may be silvered the same way. When dry, the silver
film may be polished with a piece of chamois skin, touched with
rouge, the polishing being accomplished by means of a light spiral
stroke.

Fig. 3 shows the position of the glasses in the tube, also how the
rays R from a star are thrown to the eyepiece E in the side of the
tube. Make the tube I of sheet iron, cover with paper and cloth,
then paint to make a non-conductor of heat or cold. Make the
mounting of good seasoned lumber.

Thus an excellent 6-in. telescope can be made at home, with an
outlay of only a few dollars. My telescope is 64 in. long and cost
me just $15, but I used all my spare time in one winter in making
it. I first began studying the heavens through a spyglass, but an
instrument such as I desired would cost $200--more than I could
afford. Then I made the one described, with which I discovered a
new comet not before ob