of hardwood 2 by 4 by 12 in. Round off the lower edge
of each piece to fit an old skate. Have a blacksmith bore holes
through the top of the skates and screw one of them to each of the
pieces of hardwood.

[Illustration: Plan of Ice Boat]

These skates must be exactly parallel or there will be trouble the
first time the craft is used.

Over the middle of the 6-ft. piece and at right angles to it, bolt
the 8-ft. plank, leaving 1 ft. projecting as in Fig. 1.

The rudder skate is fastened to a piece of hardwood 2 by 2 by 12
in. as the runners were fastened. This piece should be mortised 3
by 3 by 4 in. in the top before the skate is put on. Figure 2
shows the rudder post.

A piece of hardwood 1 by 6 by 6 in.

[Illustration: Details of Ice Boat Construction]

should be screwed to the under side of the 8-ft. plank at the end
with the grain running crosswise. Through this bore a hole
1-1/2-in. in diameter in order that the rudder post may fit
nicely. The tiller, Fig. 3, should be of hardwood, and about 8 in.
long.

To the under side of the 8-ft. plank bolt a piece of timber 2 by 4
by 22 in. in front of the rudder block, and to this cross piece
and the 6-ft. plank nail 8-in. boards to make the platform.

The spar should be 9 ft. long and 2-1/2 in. in diameter at the
base, tapering to 1-1/2 in. at the top. This fits in the square
hole, Fig. 1. The horn should be 5-1/2 ft. long, 2 by 3 in. at the
butt and 1 in. at the end.

Figure 4 gives the shape and dimensions of the mainsail which can
be made of muslin. Run the seam on a machine, put a stout cord in
the hem and make loops at the corners.

Figure 6 shows the way of rigging the gaff to the spar. Figure 7
shows the method of crotching the main boom and Fig. 8 a reef
point knot, which may come in handy in heavy winds.

Make your runners as long as possible, and if a blacksmith will
make an iron or steel runner for you, so much the better will be
your boat.

** Electric Rat Exterminator [358]

Some time ago we were troubled by numerous large rats around the
shop, particularly in a storehouse about 100 ft. distant, where
they often did considerable damage. One of the boys thought he
would try a plan of electrical extermination, and in order to
carry out his plan he picked up an old zinc floor plate that had
been used under a stove and mounted a wooden disk 6 in. in
diameter in the center. On this disk he placed a small tin pan
about 6 in. in diameter, bei