Marvels of Modern Science - LightNovelsOnl.com
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Now, according to the most fundamental principles of modern science, the universe contains a certain definite provision of energy which can appear under various forms, but which cannot be increased. According to Sir Oliver Lodge every cubic millimeter of ether contains as much energy as would be developed by a million horse power station working continuously far forty thousand years. This a.s.sertion is probably based on the fact that every corpuscle in the ether vibrates with the speed of light or about 186,000 miles a second.
It was formerly believed that the atom was the smallest sub-division in nature. Scientists held to the atomic theory for a long time, but at last it has been exploded, and instead of the atom being primary and indivisible we find it a very complex affair, a kind of miniature solar system, the centre of a varied attraction of molecules, corpuscles and electrons. Had we held to the atomic theory and denied smaller sub-divisions of matter there would be no accounting for the emissions of radium, for as science now believes these emissions are merely the expulsion of millions of electrons.
Radium gives off three distinct types of rays named after the first three letters of the Greek alphabet--Alpha, Beta, Gamma--besides a gas emanation as does thorium which is a powerfully radio-active substance. The Alpha rays const.i.tute ninety-nine per cent, of all the rays and consist of positively electrified particles. Under the influence of magnetism they can be deflected. They have little penetrative power and are readily absorbed in pa.s.sing through a sheet of paper or through a few inches of air.
The Beta rays consist of negatively charged particles or corpuscles approximately one thousandth the size of those const.i.tuting the Alpha rays. They resemble cathode rays produced by an electrical discharge inside of a highly exhausted vacuum tube but work at a much higher velocity; they can be readily deflected by a magnet, they discharge electrified bodies, affect photographic plates, stimulate strongly phosph.o.r.escent bodies and are of high penetrative power.
The radiations are a million times more powerful than those of uranium.
They have many curious properties.
If a photographic plate is placed in the vicinity of radium it is almost instantly affected if no screen intercepts the rays; with a screen the action is slower, but it still takes place even through thick folds, therefore, radiographs can be taken and in this way it is being utilized by surgery to view the anatomy, the internal organs, and locate bullets and other foreign substances in the system.
A gla.s.s vessel containing radium spontaneously charges itself with electricity. If the gla.s.s has a weak spot, a scratch say, an electric spark is produced at that point and the vessel crumbles, just like a Leyden jar when overcharged.
Radium liberates heat spontaneously and continuously. A solid salt of radium develops such an amount of heat that to every single gram there is an emission of one hundred calories per hour, in other words, radium can melt its weight in ice in the time of one hour.
As a result of its emission of heat radium has always a temperature higher by several degrees than its surroundings.
When a solution of a radium salt is placed in a closed vessel the radio-activity in part leaves the solution and distributes itself through the vessel, the sides of which become radio-active and luminous.
Radium acts upon the chemical const.i.tuents of gla.s.s, porcelain and paper, giving them a violet tinge, changes white phosphorous into yellow, oxygen into ozone and produces many other curious chemical changes.
We have said that it can serve the surgeon in physical examinations of the body after the manner of X-rays. It has not, however, been much employed in this direction owing to its scarcity and prohibitive price.
It has given excellent results in the treatment of certain skin diseases, in cancer, etc. However it can have very baneful effects on animal organisms. It has produced paralysis and death in dogs, cats, rabbits, rats, guinea-pigs and other animals, and undoubtedly it might affect human beings in a similar way. Professor Curie said that a single gram of chemically pure radium would be sufficient to destroy the life of every man, woman and child in Paris providing they were separately and properly exposed to its influence.
Radium destroys the germinative power of seeds and r.e.t.a.r.ds the growth of certain forms of life, such as larvae, so that they do not pa.s.s into the chrysalis and insect stages of development, but remain in the state of larvae.
At a certain distance it causes the hair of mice to fall out, but on the contrary at the same distance it increases the hair or fur on rabbits.
It often produces severe burns on the hands and other portions of the body too long exposed to its activity.
It can penetrate through gases, liquids and all ordinary solids, even through many inches of the hardest steel. On a comparatively short exposure it has been known to partially paralyze an electric charged bar.
Heat nor cold do not affect its radioactivity in the least. It gives off but little light, its luminosity being largely due to the stimulation of the impurities in the radium by the powerful but invisible radium rays.
Radium stimulates powerfully various mineral and chemical substances near which it is placed. It is an infallible test of the genuineness of the diamond. The genuine diamond phosph.o.r.esces strongly when brought into juxtaposition, but the paste or imitation one glows not at all.
It is seen that the study of the properties of radium is of great interest. This is true also of the two other elements found in the ores of uranium and thorium, viz., polonium and actinium. Polonium, so-called, in honor of the native land of Mme. Curie, is just as active as radium when first extracted from the pitchblende but its energy soon lessens and finally it becomes inert, hence there has been little experimenting or investigation. The same may be said of actinium.
The process of obtaining radium from pitchblende is most tedious and laborious and requires much patience. The residue of the pitchblende from which uranium has been extracted by fusion with sodium carbonate and solution in dilute sulphuric acid, contains the radium along with other metals, and is boiled with concentrated sodium carbonate solution, and the solution of the residue in hydrochloric acid precipitated with sulphuric acid. The insoluble barium and radium sulphates, after being converted into chlorides or bromides, are separated by repeated fractional crystallization.
One kilogram of impure radium bromide is obtained from a ton of pitchblende residue after processes continued for about three months during which time, five tons of chemicals and fifty tons of rinsing water are used.
As has been said the element has never been isolated or separated in its metallic or pure state and most of the compounds are impure. Radium banks have been established in London, Paris and New York.
Whenever radium is employed in surgery for an operation about fifty milligrams are required at least and the banks let out the amount for about $200 a day. If purchased the price for this amount would be $4,000.
CHAPTER IV
MOVING PICTURES
Photographing Motion--Edison's Kinetoscope--Lumiere's Cinematographe--Before the Camera--The Mission of the Moving Picture.
Few can realize the extent of the field covered by moving pictures.
In the dual capacity of entertainment and instruction there is not a rival in sight. As an instructor, science is daily widening the sphere of the motion picture for the purpose of ill.u.s.tration. Films are rapidly superseding text books in many branches. Every department capable of photographic demonstration is being covered by moving pictures.
Negatives are now being made of the most intricate surgical operations and these are teaching the students better than the witnessing of the real operations, for at the critical moment of the operation the picture machine can be stopped to let the student view over again the way it is accomplished, whereas at the operating table the surgeon must go on with his work to try to save life and cannot explain every step in the process of the operation. There is no doubt that the moving picture machine will perform a very important part in the future teaching of surgery.
In the naturalist's domain of science it is already playing a very important part. A device for micro-photography has now been perfected in connection with motion machines whereby things are magnified to a great degree. By this means the a.n.a.lysis of a substance can be better ill.u.s.trated than any way else. For instance a drop of water looks like a veritable Zoo with terrible looking creatures wiggling and wriggling through it, and makes one feel as if he never wanted to drink water again.
The moving picture in its general phase is entertainment and instruction rolled into one and as such it has superseded the theatre. It is estimated that at the present time in America there are upwards of 20,000 moving picture shows patronized daily by almost ten million people. It is doubtful if the theatre attendance at the best day of the winter season reaches five millions.
The moving picture in importance is far beyond the puny functions of comedy and tragedy. The grotesque farce of vaudeville and the tawdry show which only appeals to sentiment at highest and often to the base pa.s.sions at lowest.
Despite prurient opposition it is making rapid headway. It is entering very largely into the instructive and the entertaining departments of the world's curriculum. Millions of dollars are annually expended in the production of films. Companies of trained and practiced actors are brought together to enact pantomimes which will concentrate within the s.p.a.ce of a few minutes the most entertaining and instructive incidents of history and the leading happenings of the world.
At all great events, no matter where transpiring, the different moving picture companies have trained men at the front ready with their cameras to "catch" every incident, every movement even to the wink of an eyelash, so that the "stay-at-homes" can see the _show_ as well, and with a great deal more comfort than if they had traveled hundreds, or even thousands, of miles to be present in _propria persona_.
How did moving pictures originate? What and when were the beginning?
It is popularly believed that animated pictures had their inception with Edison who projected the biograph in 1887, having based it on that wonderful and ingenious toy, the Zoetrope. Long before 1887, however, several men of inventive faculties had turned their attention to a means of giving apparent animation to pictures. The first that met with any degree of success was Edward Muybridge, a photographer of San Francisco. This was in 1878. A revolution had been brought about in photography by the introduction of the instantaneous process. By the use of sensitive films of gelatine bromide of silver emulsion the time required for the action of ordinary daylight in producing a photograph had been reduced to a very small fraction of a second.
Muybridge utilized these films for the photographic a.n.a.lysis of animal motion. Beside a race-track he placed a battery of cameras, each camera being provided with a spring shutter which was controlled by a thread stretched across the track. A running horse broke each thread the moment he pa.s.sed in front of the camera and thus twenty or thirty pictures of him were taken in close succession within one or two seconds of time. From the negatives secured in this way a series of positives were obtained in proper order on a strip of sensitized paper. The strip when examined by means of the Zoetrope furnished a reproduction of the horse's movements.
The Zoetrope was a toy familiar to children; it was sometimes called the wheel of life. It was a contrivance consisting of a cylinder some ten inches wide, open at the top, around the lower and interior rim of which a series of related pictures were placed. The cylinder was then rapidly rotated and the spectator looking through the vertical narrow slits on its outer surface, could fancy that the pictures inside were moving.
Muybridge devised an instrument which he called a Zoopraxiscope for the optical projection of his zoetrope photographs. The succession of positives was arranged in proper order upon a gla.s.s disk about 18 inches in diameter near its circ.u.mference. This disk was mounted conveniently for rapid revolution so that each picture would pa.s.s in front of the condenser of an optical lantern. The difficulties involved in the preparation of the disk pictures and in the manipulation of the zoopraxiscope prevented the instrument from attracting much attention.
However, artistically speaking, it was the forerunner of the numerous "graphs" and "scopes" and moving picture machines of the present day.
It was in 1887 that Edison conceived an idea of a.s.sociating with his phonograph, which had then achieved a marked success, an instrument which would reproduce to the eye the effect of motion by means of a swift and graded succession of pictures, so that the reproduction of articulate sounds as in the phonograph, would be accompanied by the reproduction of the motion naturally a.s.sociated with them.
The principle of the instrument was suggested to Edison by the zoetrope, and of course, he well knew what Muybridge had accomplished in the line of motion pictures of animals almost ten years previously. Edison, however, did not employ a battery of cameras as Muybridge had done, but devised a special form of camera in which a long strip of sensitized film was moved rapidly behind a lens provided with a shutter, and so arranged as to alternately admit and cut off the light from the moving object. He adjusted the mechanism so that there were 46 exposures a second, the film remaining stationary during the momentary time of exposure, after which it was carried forward far enough to bring a new surface into the proper position. The time of the s.h.i.+fting was about one-tenth of that allowed for exposure, so that the actual time of exposure was about the one-fiftieth of a second. The film moved, reckoning s.h.i.+ftings and stoppages for exposures, at an average speed of a little more than a foot per second, so that a length of film of about fifty feet received between 700 and 800 impressions in a circuit of 40 seconds.
Edison named his first instrument the kinetoscope. It came out in 1893.
It was hailed with delight at the time and for a short period was much in demand, but soon new devices came into the field and the kinetoscope was superseded by other machines bearing similar names with a like signification.
A variety of cameras was invented. One consisted of a film-feeding mechanism which moves the film step by step in the focus of a single lens, the duration of exposure being from twenty to twenty-five times as great as that necessary to move an unexposed portion of the film into position. No shutter was employed. As time pa.s.sed many other improvements were made. An ingenious Frenchman named Lumiere, came forward with his Cinematographe which for a few years gave good satisfaction, producing very creditable results. Success, however, was due more to the picture ribbons than to the mechanism employed to feed them.
Of other moving pictures machines we have had the vitascope, vitagraph, magniscope, mutoscope, panoramagraph, theatograph and scores of others all derived from the two Greek roots _grapho_ I write and _scopeo_ I view.
The vitascope is the princ.i.p.al name now in use for moving picture machines. In all these instruments in order that the film projection may be visible to an audience it is necessary to have a very intense light. A source of such light is found in the electric focusing lamp.
At or near the focal point of the projecting lantern condenser the film is made to travel across the field as in the kinetoscope. A water cell in front of the condenser absorbs most of the heat and transmits most of the light from the arc lamp, and the small picture thus highly illuminated is protected from injury. A projecting lens of rather short focus throws a large image of each picture on the screen, and the rapid succession of these completes the illusion of life-like motion.
Hundreds of patents have been made on cameras, projecting lenses and machines from the days of the kinetoscope to the present time when clear-cut moving pictures portray life so closely and so well as almost to deceive the eye. In fact in many cases the counterfeit is taken for the reality and audiences as much aroused as if they were looking upon a scene of actual life. We can well believe the story of the Irishman, who on seeing the stage villain abduct the young lady, made a rush at the canvas yelling out,--"Let me at the blackguard and I'll murder him."
Though but fifteen years old the moving picture industry has sent out its branches into all civilized lands and is giving employment to an army of thousands. It would be hard to tell how many mimic actors and actresses make a living by posing for the camera; their name is legion.
Among them are many professionals who receive as good a salary as on the stage.