During the past few years competition among professional moving-picture photographers has become exceedingly keen, especially in connection with the filming of topical events. The operator often is faced with prodigious obstacles, the subjugation of which is not always easy, or even possible. For instance, in a dense crowd the conventional apparatus, from its bulkiness, weight, and proportions, cannot be handled, and, even if set upon its tripod with the lens elevated above the heads of the people, there is the serious danger of the whole being upset by the swaying motion of the mass of spectators. Yet at the same time a place in the crowd constitutes an ideal point of view.

Again, there are many situations where the use of a tripod is impracticable, if not dangerous. Take the aeroplane. An operator seated in a flying machine and desirous of recording the moving scenes beneath, cannot support his machine upon the conventional device for this purpose. He has to hold it as best he can, and so secure his pictures under extremely trying conditions. Although films innumerable are taken by persons seated in aeroplanes, only a very small proportion ever come before the public eye, for the majority are failures. Nowadays, also, the filming of aeroplane flights from a fixed point on the ground is by no means easy. In order to follow the evolutions of flying machines, more particularly at comparatively close ranges and when travelling at high speeds, two operators are required, one to turn the camera handle, and the other to sight and follow the object both through its horizontal and vertical planes in such a way as to keep it in the centre of the picture. To do this he has simultaneously to turn the two handles operating the panoramic and elevating gear of the tripod head, and often in opposite directions. The task must be done without the slightest jerk, or the success of the film is marred. One of the most disconcerting effects upon the screen is a jumpy panoramic movement either horizontally or up and down. It worries the eye, and more often than not reduces the picture to an almost unintelligible blur.

But perhaps the most unnerving and difficult conditions under which moving-pictures can be taken are those pertaining to the filming of wild animal life at close range under natural conditions. In this case a good nerve, a steady hand, and acute presence of mind, are indispensable. A wild elephant trumpeting madly and dashing towards the camera at full speed, or a lion springing towards the operator may form the subject for a thrilling incident in a film, but does not inspire confidence in the cinematographer. Under such conditions a tripod outfit is worse than useless. It not only endangers the operator's life, but the pictures taken under such conditions are invariably of poor quality, even if they survive the results of the animal's mad frenzy. To stand one's ground and to keep turning the camera handle steadily at two revolutions per second up to the last moment with the sang-froid of someone filming a street procession would put too great a strain on human nature. Even the coolest man would not obtain first-class results at uncomfortably close quarters. Instead of turning the handle in a steady rhythmic manner the motion would be in a series of erratic jerks, some fast and some slow, producing a result which the public would ridicule. Mr. Cherry Kearton, whose pictures of jungle life constitute some of the marvels of the cinematographic art, considers that this branch of cinematography cannot be excelled for thrilling excitement. The operator must stand his ground undismayed, because the close-quarter pictures are always the most fascinating. Yet at the same time he must keep a corner of one eye fixed upon an avenue of retreat, so that he can get clear in the nick of time when the crisis arises. The attention given to the photographic work must be reduced to the absolute minimum, so as to be practically automatic; the camera must be as small and as compact as possible, for the only way of escape lies often up a tree.

Several inventors have devoted their energies to the evolution of a reliable hand-camera, capable of fulfilling the same duty in cinematography as the snap-shot instrument in still-life work. The tripod was sacrificed, but then there arose another difficulty. This was in the necessity of moving the film mechanism by means of the handle. In fact, under many conditions of working, such as in the jungle, it would be quite impracticable. What was required was an efficient moving-picture machine, small, light, and compact, working upon the principle of "you-press-the-button-and-I'll-do-the-rest."

It is a perplexing problem to solve, and the first commercially practicable idea in this direction was conceived by the Polish scientist Kasimir de Proszynski. He has produced a camera completely self-contained and wholly automatic in its operation. Dimensions and weight have been kept down. In loaded condition, with 300 feet of film, it is 12 inches long, 8½ inches wide, 6½ inches deep, and weighs only 14 pounds. It works upon the "press-the-button" system, the film-moving mechanism and shutter running the whole time the button is depressed. The power comes from cylinders of compressed air by which a tiny engine is driven. All that the operator has to do is to sight his subject and to keep his finger on the button, while he follows the object on the view finder.

When this camera, known as the "aeroscope," appeared upon the market, it aroused considerable interest, but its reliability was doubted. It was not until Mr. Cherry Kearton decided to give it a trial that it came to be regarded more seriously as a feasible moving-picture machine. This naturalist-cinematographer took it with him on one of his expeditions, and was able to record some startling incidents which would not have been possible otherwise. Familiarity with the camera and experience in the field convinced him of its serviceability, provided that certain modifications were effected. These were carried out, and the camera is now regarded as an excellent instrument for work that could not be achieved by any other machine.

It is fitted, as has been said, with a small engine driven by compressed air. The air is stored in six small cylinders of an aggregate capacity of 600 feet. This is sufficient to expose 600 feet of film. The cylinders are charged with air in the manner of a motor tyre and with a similar kind of pump. An indicator on the side shows constantly the air pressure remaining in the reservoirs, while a regulator enables the speed to be varied. The driving mechanism is very light, small, and compact, and contains but a small number of parts, so that the risk of failure is not great. Though it constitutes the most delicate part of the whole mechanism, and requires careful handling, it works remarkably well so long as it is kept clean and well lubricated.

Another prominent feature of the mechanism is what is termed an equilibrator. Practically speaking this is a small gyroscope, and is introduced to subdue any small vibrations or tremblings which arise while the instrument is working. This part of the mechanism has been criticized on the ground that a gyroscope, to be effective, must be of appreciable weight. Many operators dispute the necessity for its introduction. They point out that the beneficial effects are not proportionate to the extra weight involved. Furthermore, being an additional piece of mechanism, it enhances the risk of derangement. Against these contentions, however, the operators who have worked the instrument maintain that it nullifies all the vibrations set up by the driving mechanism, which, though apparently slight, would otherwise suffice to spoil the pictures. Seeing that the sole object of employing this camera is the elimination of a rigid support such as a tripod, it certainly seems worth while, even at the cost of added weight, to gain some compensating steadiness. And the vibration of the air engine increases the need.

In operating this instrument the usual method is to hold the camera against the chest and one cheek, thereby bringing the eye on a level with the sighting piece. By letting the elbows rest against the body the weight is easily and steadily supported. Held in this position the minimum of fatigue is felt by the cinematographer, while he is given complete control over the mechanism. It can also be used when the operator is on horseback, the method of support being virtually the same. But in this case only one hand is used; the other is left free to control the horse. Another advantage of the system is the ease with which the camera can be swung round in order to follow a moving object steadily.

Photographers who use a hand-camera are familiar with the disturbances set up by the motion of the body in breathing. This is often sufficient to spoil a picture if care is not displayed at the instant of exposure. With the aeroscope—owing to the exposure being from 1/32 to 1/50 of a second, relatively long in comparison with snap-shotting where the exposure is often only the 1/200, or even less, of a second—these disturbances are somewhat more acute. Considerable practice is required before this difficulty can be overcome. Some operators who have used the aeroscope prefer to utilise a convenient support, if available, such as a wall, or the stump of a tree, thereby making sure of a solid rigid foundation. But in cinematography the ill-effects arising from respiration are not so serious as in still-life work. A picture here and there may show its effects, but they pass unnoticed. They are subdued, as it were, by the unblemished pictures which precede and follow.

Another camera of this type is the "Jury Autocam" which, as its name implies, works upon the automatic "press-the-button" system. This camera is fitted with a small electric motor, driven by a small dry battery, and brought into action by the pressure of a button. A small side-lever controls the picture-taking speed, which can be varied while the mechanism is running. The camera itself is exactly similar to the "Jury Duplex" model, the only addition being a small separate case, about 2 inches in depth, fitted to the base of the instrument, and a covered chain gearing on one side for transmitting the power from the motor to the camera mechanism. This camera likewise is fitted with a small balancing apparatus to counteract slight vibrations.

In such instruments as these the even running of the motor is a vital factor. It must not run any faster when the reservoir or battery is fully charged than when it is nearly exhausted, nor must there be any variations of speed, for eccentricities of this sort are apt to spoil the film. The governing therefore requires to be most delicate and thorough. Another difficulty is the incorporation of a reservoir capable of carrying a sufficient quantity of air at the necessary pressure to drive the length of film for which it is rated. In the "Jury Autocam" a length of 100 feet can be driven on a single battery charge. This is adequate for many purposes, but a length of at least 200 feet is generally to be preferred. The camera is being adapted to meet these conditions, and it is anticipated that no more difficulty will be met in consummating this end, than was involved in making the camera drive a 100 feet length.

While it is a moot point whether the automatic cinematograph camera will ever displace the orthodox machine entirely, it is a useful and even indispensable machine for working under difficulties. It has been used in the aeroplane and has been found successful. It is also of the utmost use in close-range dangerous work, or in situations where the turning of the handle by hand is liable to be carried out imperfectly and unsteadily. The aeroscope camera has been used on many notable expeditions such as those of Paul Rainey, and others in Africa, and is used exclusively by Mr. Cherry Kearton in his daring work in tight corners. Many of the thrilling and exciting pictures taken in the haunts of wild animals have been secured therewith, and these films show convincingly what can be done with the instrument when it is handled by an expert.

But the true province of the hand cinematograph camera undoubtedly is in connection with rush work. For the filming of topical incidents it is invaluable. The operator is not trammelled with a bulky outfit. He carries his camera in his hand or slings it across his back in the manner of a knapsack. When he wishes to film an incident he is not harassed even by the crowd. He is not compelled to set up a tripod or to climb to an elevated point to get clear of the sea of heads. He can hold the camera above his head, and by means of a second and special view finder placed on the under side of the instrument he can sight and follow the subject while pressing the button. Thus he records the episode as easily as if he were placed in the most advantageous raised position, and could manipulate the machine in the orthodox manner. When his work is completed he can get away without any delay, because the small box contains everything.

On the whole, however, the hand moving-picture camera is scarcely yet a suitable instrument for beginners. The invention is in its infancy, and although clever men are striving to make it more simple and reliable, many peculiar problems still remain to be solved. But in the hands of an expert operator it is capable of doing first-class work.