o for each jar. Their
size also depends on the voltage. The disks that are placed in the
lower part of the jars are connected with a rubber covered wire
extending a little above the top of the jar.

To wire the apparatus, refer to the sketch and you will see that
jar No. 1 is connected to point No. 1 on switch; No. 2, on No. 2,
and so on until all is complete and we have one remaining point on
switch. Above the jars place a wire to suspend the other or top
disks in the solution. This wire is also connected to one terminal
on the motor and to remaining point on switch. The arm of the
switch is connected to one terminal of battery, or source of
current, and the other terminal connected direct to remaining
terminal of motor.

Put arm of switch on point No. 1 and lower one of the top disks in
jar No. 1 and make contact with wire above jars. The current then
will flow through the motor. The speed for each point can be
determined by lowering top disks in jars. The top disk in jar No.
2 is lower down than in No. 1 and so on for No. 3 and No. 4. The
connection between point No. 5 on switch, direct to wire across
jars, gives full current and full speed.

** How to Build a Toboggan Sled [44]
By A. BOETTE

The first object of the builder of a sled should be to have a
"winner" both in speed and appearance. The accompanying
instructions for building a sled are designed to produce these
results.

The sled completed should be 15 ft. 2 in. long by 22 in. wide,
with the cushion about 15 in. above the ground. For the baseboard
select a pine board 15 ft. long, 11 in. wide and 2 in. thick, and
plane it on all edges. Fit up the baseboard with ten oak
foot-rests 22 in. long, 3 in. wide and 3/4 in. thick. Fasten them
on the under side of the baseboard at right angles to its length
and 16 in. apart, beginning at the rear. At the front 24 or 26 in.
will be left without cross bars for fitting on the auto front. On
the upper side of the cross bars at their ends on each side screw
a piece of oak 1 in. square by 14 ft. long. On the upper side of
the baseboard at its edge on each side screw an oak strip 3 in.
wide by 3/4 in. thick and the length of the sled from the back to
the auto front. These are to keep the cushion from falling out.
See Fig. 1. For the back of the sled use the upper part of a
child's high chair, taking out the spindles and resetting them in
the rear end of the baseboard. Cover up the outside of the
spindles with a