e into pulp to fill the
space H, Fig. 4. The plate, Fig. 1, is held to the base by two
screws which are run through the holes BC and take the position
shown by DD, Fig. 4.

The two binding-posts are attached on the base at D, Fig. 2, also
the switch B and the fuse block C, holes being bored in the base
to make the wire connections. The reverse side of the base, with
slits cut for the wires, is shown in Fig. 3. The points marked BB
are the glass tubes; AA, the holes leading to the switch; and C,
the fuse block. The wires run through the glass tubes GG, Fig. 4,
are allowed to project about 1 in. for connections.

The best way to find the correct length of the resistance wire is
to take a large clay or drain tile and wind the wire tightly
around it, allowing a space between each turn. The tile is then
set on its side with a block or brick under each end. It should
not be set on end, as the turns of the wires, when heated, will
slip and come in contact with each other, causing a short circuit.
When the tile is in place, a short piece of fuse wire is fastened
to each of its two ends. A 5-ampere fuse wire is about strong
enough. A connection is made to these two wires from an
electric-light socket. The wire will get hot but probably remain
the same color. If this is the case, one of the feed wires is
disconnected from the fuse wire and gradually moved farther down
the coil until a point is found where the resistance wire glows a
dull red. This point marks the proper length to cut it, as the
wire should not be allowed to become any hotter. If the wire gets
bright hot when the current is turned on, more wire should be
added. The wire is then made into a long coil by winding it around
a large wire nail. The coils should be open and about 1/8 in.
apart.

Next, the fire clay is moistened and well mixed, using care not to
get it too wet. It should have the proper consistency to mould
well. The clay, II, Fig. 4, is then packed in the first plate to a
height of about 1/4 in. above the rim. While the clay is damp, one
end of the coil is connected with the wire in the central glass
tube, and the coil laid in a spiral winding on the damp clay, KK,
and pressed into it. When this is done, the other end is connected
to the wire projecting from the outer glass tube. As these
connections cannot be soldered, the ends of the wires should be
twisted closely together, so that the circuit will not become
broken. Make sure that the coils of