Within the past two or three years the idea has come into vogue of accompanying movements in the pictures with characteristic sound effects. When a horse gallops, the sound of its feet striking the road are heard; the departure of a train is accompanied by a whistle and a puff as the engine gets under weigh; the breaking of waves upon a pebbly beach is reproduced by a roaring sound. Opinion appears to be divided as to the value of the practice. Some more cultivated motion photography lovers opposed to it, on the ground that unless every motion is given its distinctive sound, none at all should be audible; others contend that sound imparts an additional realism to the scene. There is no doubt that at times the sound effects come as an unpleasant and disturbing shock, especially when they are neither in time nor harmony with the motion - for example, when the realism of a mediaeval battle is heightened by the vigorous rattling of a machine gun, or when horses galloping over the turf make a clatter that only a city pavement could cause.

But, on the other hand, since sound effects ar indispensable to the legitimate stage, why should they not be extended to the moving picture theatre? What would Macbeth be without the crashing of thunder, and how could the impression of rattling hail, or the howling and shrieking of the wind, be conveyed without recourse to various devices in the wings? Even if the play be in pantomime, all sound is not suppressed. The players may be mute, but yet one hears the slam of a door, or the crash of an overturned chair as it strikes the floor, and so on. Accordingly it would seem that sound effects are perfectly justifiable in moving pictures, provided they are judiciously managed.

The first attempts to introduce sound effects provoked humorous situations. The boy deputed to the task enjoyed the chance to make noise, and applied himself with a vigour of enthusiasm which overstepped the bounds of common sense. Nowadays such effects are employed with all the care and discrimination expended on the picture themselves, and the result is harmonious and pleasing.

Of course, it has been necessary to devise all sorts of contrivances for realistic sound production, from the firing of a 12-inch gun to the squeak of a mouse. The most interesting of these is the "Allefex", invented by Mr. A. H. Moorhouse. It is the most comprehensive and ingenious machine ever made for the mimicry of sound, for although it measures only four feet in height, by about three feet in width and depth, it produces some fifty characteristic sounds, including the howl of a storm, the rushing of waterfalls, the bark of a dog, and the twittering of birds. Every artifice for producing these noises is contained within a small cubical space, and the operation has been so simplified that one man is sufficient for the task.

A general impression of this machine may be gathered from the illustration. It appears to be a maze of levers, cranks, plug-holes, and bulbs, but each attachment performs some definite purpose and produces one or more distinct sounds. Another striking feature is that its operation demands the minimum of practice, for the majority of the effects are produced by straightforward action. It is only here and there that a little practice is required, such as, for instance, to imitate the bark of a dog, or the cry of a baby.

It would be impossible to describe in one chapter all the various effects produced by means of this apparatus. I will confine myself, therefore, to some of the more difficult sounds, many of them apparently beyond the reach of mechanical mimicry. The shot of a gun is imitated by striking a drum at the top of the machine, on which a chain mat has been placed, a smart blow with a felt drumstick as near as centre as possible. The same device serves to represent successive shots. The interior of the drum is fitted with three drum-sticks, which are manipulated by the turning of a handle, the number of shots varying, with the speed, according to the picture. At the bottom of the machine is a large bellows worked by the foot. Their manipulation in conjunction with one or other of the handles will produce the sound of exhaust steam issuing from a locomotive, the rumbling of a train rushing through a tunnel, and so on. Running water, rain, hail, and the sound of rolling waves are obtained by turning o handle, which rotates a ribbed wooden cylinder against a board set at an angel from the top of which hang a number of chains. By varying the speed of the cylinder any of the above sounds may be obtained with accuracy. The puffing of an engine is made by revolving a cylinder with projections against a steel brush; the crash of china, pots and pans, &c., is due to the revolution of a shaft on which are mounted a series of tappets striking against hammers, which in turn come into contact with a number of steel plates. The crackling of a machine gun is caused by turning a shaft having tappets which strike and lift up wooden laths, subsequently releasing them to strike smartly against the framework of the machine. The same device also serves for imitating the crash attending the upsetting of chairs, tables, and so on. Pendant tubes serve to produce the effect of church bells, fire alarm, ship's bell, and similar noises; the sound of trotting horses is caused by revolving a shaft carrying three tappets which lift up inverted cups. This shaft is slightly movable, so that by adjustment a trot can be converted into gallop and vice vercâ, while distance effects are obtained by a muffling attachment. Thunder is made by shaking a sheet of steel hanging on one side of the machine; the press of a bulb gives the bark of a dog; the bellows and another attachment operate the warbling bird; while the cry of the baby is emitted by the dexterous manipulation of plug-hole and bellows.

A machine like this is a distinct acquisition to the modern picture theatre, for when skillfully controlled it provides a scientific and perfect mechanical apparatus for the production of distinctive sound, correctly, and at the proper moment. At the same time, it is so simple that little practice is demanded to make the operator expert in the art of mechanical mimicry.

Source: Moving Pictures - How they are made and worked,
written by Frederick A. Talbot
Publ. William Heinemann, London, 1912