Owing to difficulties not yet overcome moving X-ray pictures cannot be taken of the human body at this time. Röntgen rays cannot be refracted, or collected in a lens. Hence the film for an X-ray picture must be equal in size to the picture desired. It is impossible to increase the size of cinematograph films with much success because of the danger of breaking or tearing them when under the strain of the rapid course they must pursue through camera and projector. These facts made it necessary for the scientists experimenting with X-ray motion pictures to photograph only animals, but they were greatly encouraged because they obtained some excellent views of the digestive processes of mice, guinea-pigs, fowls, and other small animals. The bones of the human hand also were photographed while the hand was opened and closed.
M. J. Garvallo, who carried on a great many interesting experiments in France with this type of motion pictures, used a somewhat larger and more sensitive film than the standard, combined with an apparatus too complex for attention here. This phase of cinematography, however, is still in its infancy and we can look for great improvements at an early date.
Another Frenchman, Prof. Lucien Bull, who was one of Doctor Marey's assistants in the early stages of cinematography, has made pictures of the movement of the wings of various insects such as flies, bees, wasps, etc. To do this he has had to make the fastest known cinematograph. It was an especially constructed apparatus entirely unlike the ones described here, but through the agency of an electrical spark which illuminated the vicinity in which the insect flew, 2,000 pictures per second were taken, instead of the usual sixteen.
The very antithesis of the scientific are the uses of the motion-picture film as an illustrated magazine or newspaper. There are only a few successful "animated newspapers" in the world, but the idea will probably spread. The staff of such a publication is made up of photographers, who are scattered about in every nation on the globe. There are regular offices in all the big cities which are ready at a moment's notice to send photographers to any part of their territory. These photographers get films of all the important news occurrences of the day, parades, street demonstrations, wrecks, fires and whatever else fills the newspapers you read every day. The films are hurried to the main office where they are developed, cut down to short "items," or allowed to run as long, "stories" just like in a regular newspaper, pasted together with suitable headlines, printed in one continuous roll of about 1,000 feet and rushed out to the subscribers, who are usually theatres with audiences eager for the "paper."
Such are a few of the many motion-picture activities which have sprung up in the last few years, and made it possible for us to see whatever is interesting in any part of the world, on the cinematograph screen. Beside the professional cinematographers, there are of course any number of smart boys and young men who are having fine times with the amateur projecting outfits sold by the big makers of apparatus. These machines run from mere toys made up for a little roll of film, already prepared, to projectors with which very creditable parlour shows can be given.
CHAPTER VII
STEEL BOILED LIKE WATER AND CUT
LIKE PAPER
OUR BOY FRIEND SEES HOW SCIENCE HAS TURNED THE GREATEST KNOWN HEATS TO THE EVERYDAY USE OF MANKIND
"HOW hot is it in that furnace?" asked the scientist's young friend as he poked about the laboratory one day.
"That is not very hot now, but we could increase the temperature to about 4,000 degrees Fahrenheit if we tried hard enough," answered the man who, outside of his work, enjoyed best of all the visits of the boy. "But the heat of the laboratory furnace most of the time is nothing compared to the heat that we can put to practical use through a couple of new inventions I have been trying here."