your mouth wider and keep it open longer than for the first syllable.

EXPERIMENT 125.-This is all we have to know to make our toy trumpet talk. You already have seen that its sounds, like those of the human voice, are made by puffs of air. These pass the reed every time it goes above or below the oblong hole in the plate in which it vibrates. Your experiments with König's flame have told you that the sounds of the voice and trumpet are similar—that both are highly composite.

Let, then, the vibrating reed in the trumpet stand for your vocal chords. To get a resonant cavity like the mouth, make one between your two hands, as shown in A of Fig. 58. The funnel of the trumpet is placed inside this cavity, with the tube coming out in the crotch between the thumb and forefinger. The lips we will form of the fingers of one hand. By raising these together, more or less, from the other hand we can make a larger or smaller opening into the cavity between the palms of the hands, and thus get articulation.

Now blow into the trumpet as though you were speaking mama into it, so that you may make it sound twice, each sound lasting just as long as the sounds in mă and mă. While making the first sound, raise the fingers as high as is shown in A; while making the second, raise them as high as is shown in B. The trumpet talks and says mama quite plainly.

EXPERIMENT 126.-Let us make a talking machine. Get an orange with a thick skin and cut it in halves. With a sharp dinner-knife cut and scrape out its soft inside. You have thus made two hemispherical cups. Cut a small semicircle out of the edge of each cup. Place these over each other, and you have a hole for the tube of the trumpet to go out of the orange. Now sew the two cups together, except a length directly opposite the trumpet, for here are the lips. A peanut makes a good enough nose for a baby, and black beans make "perfectly lovely" eyes. Take the baby's cap and place it on the orange, and try if you can make it say

FABER'S TALKING MACHINE.

These simple experiments show the principles followed in the construction of the celebrated talking machine of Faber of Vienna. A vibrating ivory reed, of variable pitch, forms its vocal chords. There is an oral cavity whose size and shape can be rapidly changed by depressing the keys on a key-board. Rubber tongue and lips make the consonants. A little windmill turning in its throat rolls the r, and a tube is attached to its nose when it speaks French. This is the anatomy of this really wonderful piece of mechanism.

EDISON'S TALKING PHONOGRAPH.

From the above description it is seen that Faber worked at the source of articulate sounds, and built up an artificial organ of speech, whose parts, as nearly as

Edison. He attacked the problem, not at the source of origin of the vibrations which make articulate speech, but, considering the vibrations as already made, it matters not how, he makes these vibrations impress themselves on a sheet of metallic foil, and then reproduces from these impressions the sonorous vibrations which made them.

Faber solved the problem of making a machine speak by obtaining the mechanical causes of the vibrations making voice and speech; Edison solved it by obtaining the mechanical effects of these vibrations. Faber reproduced the movements of our vocal organs; Edison reproduced the motions which the drum-skin of the ear has when this organ is acted on by the vibrations caused by the movements of the vocal organs.

Figs. 60 and 61 will render intelligible the construction of Mr. Edison's machine. A cylinder, F, turns on an axle which passes through the two standards A and B. On one end of this axle is the crank D; on the other, the heavy fly-wheel E. The portion of this axle to the right of the cylinder has a screw-thread cut on it which, working in a nut in A, causes the cylinder to move laterally when the crank is turned. On the surface of the cylinder is scored the same thread as on its axle. At A (shown in scale in Fig. 61) is a plate of iron about inch thick. This plate can be moved toward and from the cylinder by pushing in or pulling out the lever I G, which turns in a horizontal plane around the pin I.

The under surface of this thin iron plate (A, Fig. 61) presses against short pieces of rubber tubing, X and X, which lie between the plate and a spring attached to E. The end of this spring carries a rounded steel point, P, which, when brought up to the cylinder by the motion of

the handle H, enters slightly between the threads scored on the cylinder C. The distance of this point, P, from the cylinder is regulated by a set-screw, S, against which abuts the lever H G. Over the iron plate A is a disk of

The under

side of this disk nearly touches the plate A. Its upper surface is cut into a shallow, funnel-shaped cavity leading to the opening in its centre.