[Illustration: Instrument for Locating Stars]
The instrument is mounted on a tripod or piece of iron pipe
carrying a short vertical rod of 3/8-in. steel. A rectangular
wooden frame with suitable bearings rotates about this shaft. The
frame has also two horizontal bearings carrying a short shaft to
the end of which the frame carrying the hour axis is firmly
clamped. By this arrangement of two perpendicular shafts the hour
axis may be directed to any point in the heavens without care as
to how the tripod or pipe is set up.
The frame for the hour axis is about 12 in. long with a bearing at
each end. The shaft which it carries is 1/4-in. steel, carrying
the hour circle at one end, and at the other the frame for the
declination axis which is similar to the other, but somewhat
lighter. The declination axis is also of 1/4-in. steel, carrying
at one end the declination circle and the pointer at the other.
The entire frame of the instrument is made of cherry and it will
save the builder much time if he will purchase cherry "furniture"
which is used by printers and can be obtained from any printers'
supply company.
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