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 observed by astronomers.
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