ose
elevation above the horizon is equal to the latitude of the
observer's station. The final adjustment of an ordinary equatorial
is very tedious so that when once set up it is not to be moved.
This calls for a suitable house to protect the instrument. It has
been the aim of the writer to build a very simple instrument for
amateur work which would be adjustable to any latitude, so easily
set up ready for work and so portable that it need not be left out
of doors from one evening until the next.

[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. It is best quality wood free from imperfections in
straight strips one yard long and of a uniform width of about 5/8
in. As to thickness, any multiple of 12-point (about 1/8 in.) may
be obtained, thus saving much work in fitting up joints. Fifty
cents will buy enough wood for an entire instrument. All corners
are carefully mortised and braced with small brass angle-pieces.
The frame is held together by small brass machine screws. After
much experimentation with bearings, it was found best to make them
in halves as metal bearings are usually made. The loose half is
held in place by guides on all four sides and is tightened by two
screws with milled nuts. A great deal of trouble was experienced
in boring out the bearings until the following method was devised.
One hole was bored as well as possible. The bearing was then