Illustration: The Wind Vane, Magnets and Indicator]

eight 4-ohm magnets fastened upon a l-in. board. These magnets are
placed in a 10-in. circle, 45 deg. apart and with their faces
pointing toward the center. Covering these is a thin, wood board
upon which is fastened a neatly drawn dial resembling a mariner's
compass card. This is placed over the magnets in such a manner
that there will be a magnet under each of the eight principal
points marked on the dial. Over this dial is a magnetic needle or
pointer, 6 in. long, perfectly balanced on the end of a standard
and above all is placed a cover having a glass top. The eight
wires from the timer contacts connect with the outside wires of
the eight magnets separately and the inside wires from the magnets
connect with the metal brace which holds the magnets in place. A
wire is then connected from the metal brace to a push button, two
or three cells of dry battery and to the ground wire in connection
with the timer The wires are connected in such a manner that when
the vane is pointing in a certain direction the battery will be
connected in series with the coil under that part of the dial
representing the direction in which the vane is pointing, thus
magnetizing the core of the magnet which attracts the opposite
pole of the needle toward the face of the magnet and indicating
the way the wind is blowing. The pointer end of the needle is
painted black.

If the vane points in such a direction that the timer brush
connects two contacts, two magnets will be magnetized and the
needle will point midway between the two lines represented on the
dial, thus giving 16 different directions. Around the pointer end
of the needle is wound a fine copper wire, one end of which
extends down to about 1/32 in. of the dial. This wire holds the
needle in place when the pointer end is directly over the magnet
attracting it; the magnet causing the needle to "dip" will bring
the wire in contact with the paper dial. Without this attachment,
the needle would swing a few seconds before coming to a
standstill.

The vane itself is easily constructed as can be seen in the
illustration. It should be about 6 ft. long to give the best
results. The magnets used can be purchased from any electrical
store in pairs which are called "instrument magnets." Any
automobile garage can supply the timer and an old valueless
bicycle frame is not hard to find. The cover is easily made from a
picture frame with four s