u will be
obliged to buy or borrow, although a great deal can be done with a good
knife. Do not be satisfied with rough-looking pieces of apparatus.

There are a few important tools needed for this work. While substitutes
can be found for most of them, the boy who has access to a wood-working
bench and tools will be able to do better and more rapid work than the
boy who has no such tools.

283. List of tools. The following tools are needed, if rapid, accurate
work is desired:

(1.) Lead pencil. (2.) A rule, divided into sixteenths for measuring. A
straight foot rule will do,--cost one cent. (3.) Steel point for
scratching lines on tin and copper. A stout needle-point is just the
thing. (4.) An awl for making holes in wood; one that is a little less
than 1/8 in. in diameter is best. (See App. 25.) (5.) A try-square with
a 6 in. blade, so that you can mark out your apparatus with square
corners. You can use a square-cornered box or piece of pasteboard, if
you have no try-square. (6.) Chisels are very useful, but you can do
wonders with a good sharp knife. (7.) Screw-driver. Do not use a good
knife-blade for a screw-driver. (8.) A saw, one with teeth that are not
too coarse is to be preferred. (9.) A plane is extremely useful to make
your wood-work smooth and neat; but a great deal can be done with the
sharp edges of broken glass, followed by a good rubbing with fine
sand-paper. (10.) A brace and a set of bits may be needed in 2 or 3
cases, but nearly all of the holes can be made as in App. 25. (11.)
Punches for sheet-tin, etc., will save much time. (See App. 26, 27.) For
small holes in binding-posts, etc., use a flat-ended punch, 1/8 in. in
diameter. You should have one 1/4 or 5/16 in. in diameter, if you make
your yokes, armatures, etc., as in Chapter VIII. A blacksmith will help
you out with this. (12.) A center-punch or sharp-pointed punch for
making dents in metal. A sharp-pointed wire nail will do for tin and
copper. (13.) Files for metal. (14.) Some sort of a vice or clamp. (See
App. 79, 80.) (15.) Shears for cutting sheet-tin, etc. A pair of old
shears will do. (16.) An anvil or piece of old iron that may be used to
hammer on to flatten tin, etc. An old flat-iron makes a good anvil.
(17.) Hammer.

The small hollow handle tool sets are very handy, and they contain small
chisels, awls, screw-driver, etc. These sets cost from 50 cents up.

_284. Materials._ For wood you will find the sides and ends of clean
soap