The trumpets sold in the shops, as a rule, make a very loud noise
indeed--in fact, a little of it goes a very long way with most people.
The increased sound is probably due to the body of the trumpet being
composed of brass, which, vibrating in unison with the ferrotype plate,
increases the sound. Wood will therefore not give so loud a sound, and
if you can construct the case of metal you should certainly do so. The
vibrations of the plate, and therefore the sound, may also be increased
by using a horseshoe magnet, the two poles attracting the plate more
strongly. In the bought trumpets the case is shaped like a horn, in
which the magnet is placed, the platinum contact-breaker being behind
(where it is in the one I have described, supposing there was no bottom
to the box and the magnet was supported by a bar across from side to
side, the cornucopia being placed on that side of the box, instead of
the other, with the magnet inside it). I think it is unnecessary to
describe their construction further, as the principle and details of
construction of the simple one I have described will apply to any, and
any method of structure may be adopted which suits the mind of the
maker.
The trumpet having been made I will now give you a plan of fitting it
up which adds enormously to the effect. We want to hide the trumpet so
that no one shall know where it is. My own plan of doing this is as
follows: I have made a wooden erection, of which I give a drawing which
will explain itself. It consists of a back with a shelf at the bottom
and a kind of canopy at the top. It can be made almost any size, small
or big, to suit the occupant of the shelf. My own measurements are
about as follows: From the top A to the bottom B, the length of back
piece, including bracket, 1 foot 3 inches. Breadth of back 5¼ inches.
Side of canopy (D), breadth 4½ inches, height 3½ inches, breadth of
front (C to D) 5¼ inches; height of course the same as sides. The
top piece will then be about 5¼ inches by 4½ inches. The shelf at
the bottom is about the same size as the top of the canopy, and is
supported by a bracket of rather thick wood, which you can carve as
elaborately as you like.
Now take the electric trumpet, whether made at home or purchased, and
fasten it to the under side of the canopy (this is best done before
the sides are put on), and fasten a double wire behind the back
(cutting a groove for it to go in) up to the back of the canopy, where
it goes through and divides, one wire being fastened to one terminal
of the trumpet and the other wire to the other. The double wire goes
right down the back and emerges at B. Obviously if you now join your
press and battery on to the double wire, when you squeeze the press
the trumpet will squeak. But here we are going to practice a little
innocent deception, and to that end we go to a toy shop and purchase
a small and pretty doll of the male sex, and if you can get one (or
dress one up) attired as a soldier or trumpeter, by all means do
so. The doll is now to be fixed on to the bracket by means of a long
wire--say a hairpin bent out straight, one end being pushed into the
wood, the other passing up one trouser leg of the doll and into its
body; the wire is thus completely hidden and is much better than glue,
as it admits of the doll being placed in a natural attitude, and being
removed if required. In one of his hands you must make him hold a small
trumpet (this is a very expensive item; it will cost two cents) with
the mouthpiece to his mouth, as represented in the picture.
[Illustration: FIG. 4.--ELECTRIC DOLL.]
The whole thing is now fastened to the wall in a convenient place,
by driving nails through the back, and the double wire is completely
hidden by passing it behind furniture, books, etc., down to the floor.
There is great scope for ingenuity on the part of the worker in hiding
the wire, and no definite instructions can possibly be given. In my own
case I have no back piece below the shelf the support being against
the wall. The wire descends behind the support (to B in the picture),
and below that I have hung a "date calendar" over it, it makes a turn
to the right and goes down behind a chiffonier covered with books to
the floor. Under these circumstances no human being could possibly tell
that there was a wire at all, and there being no back piece under the
bracket (so that the paper of the room can be seen), nothing but the
support touching the calendar, it does not look as if any wires could
possibly be hidden anywhere.
Now, if you press the button, of course the trumpet squeaks, but the
doll being just underneath it, and the trumpet being in the dark under
the canopy, no one thinks it is a separate instrument, but of course
every one jumps to the conclusion that it is the doll blowing! Hide the
battery in a corner in a black box, the wires coming through the side
next the wall, and the press in a dark corner, or on the floor under a
table so that you can put your foot on it while your hands are free,
writing, etc.
You can of course now tell the doll to blow, at the same moment putting
your foot on the press, when the trumpet blows accordingly. Of course
this is mysterious to the last degree to the uninitiated friend to whom
you are displaying the doll, as you may be any distance off from the
doll with your hands free, speaking to him across the room.
The wooden erection to hold the doll can be painted any color;
preferable the back should be _black_, as it shows off the doll. In
front of the canopy you can paint a monogram or heraldic device. If
the doll is one of those extremely pretty little specimens which can
be procured at any good toy shop for about twenty-five cents, dressed
as base ball players, soldiers, etc, (what our grandmothers would
have thought of them in their young days it is difficult to imagine)
it will really be quite an ornament to the room, independently of its
electrical qualities.
This chapter has outgrown the space I meant to occupy, and I must wait
for the next to tell you how to make the doll work from various parts
of the room as you walk about and talk to him, and how to make the
battery. The best battery to use is to _Leclanche_. You can use three
or four cells of No. 2 size according to length of wire through which
the current has to pass.
In my next chapter I will try and explain how to make an electric
_drum_, so that you can have a kind of drum and fife band.