Science has recently discovered a "new thing under the sun" in the X-ray, or Roentgen ray, or cathode light, as it is sometimes called. This is a weird property of electricity, which enables one to see partly through solid objects, and has been of great service to science in locating dislocations, breaks in bones and bullets in human bodies, besides being put to other uses since its great power was discovered.

As long ago as 1857 Dr. Heinrich Geissler, a celebrated German scientist, who learned the trade of glassblower, made some glass tubes from which the air had been exhausted. The tubes were made of thin glass and in each end platinum wires passed through to the inside of the tube. These tubes are still known as Geissler's tubes, and for years have been used to illustrate the phenomenon which accompanies the discharge through them of highly rarefied gases and vapors.

These tubes vary in size from a small quarter-inch cylinder, three or four inches long, to tubes two inches in diameter and ten inches long. They are made in several shapes, to meet the needs or whims of the user. The platinum wires which lead into the tube are usually tipped with small spears or disks of platinum or aluminum. These tubes contain air in various degrees of rarefaction; that is, the air in some tubes is more completely exhausted than in others, and thus the tubes approach more nearly a perfect vacuum. When the terminals—the wires leading from the positive and negative poles—of the secondary coil of an ordinary induction coil are connected with these "electrodes"—the platinum wires in the ends of the tube— and an electric current is sent over the wires, various colored light effects take place inside of the tube. These depend upon the degree of air rarefaction, and also of the kind of gas that is put into the tubes; for, sometimes, after the air has been exhausted, the tube is filled with hydrogen, nitrogen, carbonic acid gas and other gases.

By courtesy of W. Scheidel & Co., Chicago Bones of the foot as seen through a shoe by means of the X-Ray.

The induction coil is an apparatus which has two coils of wires. The inside coil is made of thick, heavy wire, and the other coil, which entirely surrounds the inside coil, is made of thin wire. The inside coil is called the "primary" coil and has but few turns of the heavy wire. The outside coil is called the "secondary" coil, and is made with many hundred turns of very fine wire. The two coils are not connected with each other in any way, but if a current is made to flow through the "primary-coil" it "induces" a current in the "secondary" coil. The battery connected with the primary coil may produce a large current with little force. It will induce in the secondary coil a small current of very great force, or, as we say, "the electro-motive force of the induced current will be higher than that of the primary current." When this induced current is sent through a Geissler's tube, the tube is filled with different colored lights. If the degree of rarefaction is not very high, lustrous layers of light, separated by dark bands, are produced throughout the tube. If the tube is filled with rarefied air the color of the bands will be a rosy red; if filled with nitrogen gas, an orange-yellow light will be produced. Hydrogen gas will make a pale bluish color, and carbonic acid gas will give a light that is a pale green.

By courtesy of W. Scheidel & Co., Chicago The bones of the foot, as shown by the X-Ray.

The bands of light that are seen in the tube are curved, and the concave surfaces are nearest the positive electrode. These bands extend nearly the whole length of the tube, but between them and the negative electrode is a dark space, while immediately surrounding the negative electrode is a beautifuI pale-blue glow. As the rarefaction in the tube is carried further and further, the light from the positive end of the tube tends more and more to fill the tube, although in general receding from the negative end. At the same time the beautiful lavender glow from the negative end spreads more and more, filling more of the space around the negative electrode. If the rarefaction is carried still higher, the positive light which now occupies a considerable part of the tube and takes more or less the shape, of the enclosing vessel, divides up into any number of cup-shaped layers at right angles to a line drawn through the center of the tube, the long way. These layers are separated from each other by darker intervals, and their concave sides are turned toward the positive electrode. Although the positive light changes with the increased rarefaction of the air, the negative light remains substantially constant. The lavender light around the negative electrode is still the same, being uniform., but is more intense and spreads over more space. These rays from the negative pole shoot across the tube in straight lines, and striking upon the glass walls of the opposite side, produce a most brilliant fluorescence. If a screen of mica be put in the path of these negative rays, it stops them, and the shadow of the screen is outlined on the glass walls of the tube, surrounded by a bright fluorescence. The negative is called the "anode," and the negative electrode the "cathode." Thus the name of cathode ray is given to the negative light in the Geissler tube.

The Crookes tube, in outward appearance, is not different from a Geissler, but the air in the former is always exhausted to a much higher degree than in the latter. The exhaustion has been carried as high as 1-20,000,000 of an atmosphere. When it is remembered that one atmosphere will sustain a column of mercury thirty inches in height, and exerts a pressure of about fifteen pounds to the square inch, one can but vaguely imagine the exceedingly small quantity of air that is left in a tube so exhausted.

When a magnet is brought near a Crookes tube, the positive light is rotated by the magnetic influence, but the cathode rays act differently. If the negative (cathode) end of the tube is placed over the space between the poles of a horse-shoe magnet, the lavender glow around the negative electrode, seemingly, will be drawn to one side, and an arch reaching from pole to pole in the tube will be made, with the concave face toward the two poles of the magnet. Now, the X-rays come from the cathode end of the tube, but they are not what we call cathode rays, for, it has been proved that a magnet has no influence on the X-rays, which pass straight through the magnetic field, even though the cathode rays are deflected by the magnet. The X-rays will pass through a book or a board and brighten a phosphorescent screen, or they will go through leather, flesh, wood, paper, cloth, and other things that cannot be penetrated by ordinary light, and act upon a sensitive photographic plate. Sometimes the Crookes tube is of bulbed or globular shape, and sometimes it is shaped like a Geissler tube. When it is used to make an X-ray "shadowgraph," the electric current is automatically broken many times a second, and this increases the intensity of the light.

Since the discovery of the power of the X-rays- scientists have developed it greatly. Now, it is possible to watch a man's heart beat through his body and clothing, or to take photographs of interior organs of the body or substances lodged in them. Of course, these photographs are only dimly outlined as their name, "shadowgraph," would indicate. Yet they have been of great value in saving life and in directing surgical operations. When a shadowgraph is to be taken, the subject is stretched over a photographic plate holder containing a sensitive plate. Then the X-ray machine is set to working, the rays pass through the body upon the plate within the holder and expose it after the fashion of picture taking. The rest of the process is just like that in finishing photographs.

When the X-rays were discovered by Roentgen, of Würtzburg, there were very few pieces of apparatus suitable for the production of the rays. Since that time, manufacturers of both coils and static machines have increased in number until now there are fully twenty reliable firms in this country alone. In Chicago, four or five good static machines are manufactured, and a larger number of good induction coils.

Among the static machines those of C. F. Birtman & Co., and N. 0. & Co., are not only beautiful to look upon but are efficient as energizers of the X-ray tubes. These machines are of the same general type. The X-ray furnished by these machines is excellent for fluoroscopic examination. The patient is placed near the X-ray tube so that the rays will pass through the body. The fluoroscopic screen will be lighted up by the X-rays that pass through the body of the patient. The thicker parts obstruct the ray more than the less dense parts, and thus a shadow is cast upon the fluoroscopic screen. This screen is ordinarily closed in a hood which has a sort of oval aperture. The margin of this aperture is covered with lamb's fleece, and will accommodate that part of the face surrounding the eyes. When the rays are not in action, the operator will be looking into a perfectly black box, but as soon as the rays are generated, the screen is lighted up in the manner described above.

By courtesy of W. Scheidel & Co., Chicago. The bones of a hand as seen by the X-Ray.

Of the good induction coils in this city we shall mention those of Scheidel & Co., and the Western X-ray. These coils when attached to a 110 volt circuit will give a continuous spark of deafening sound over a gap of twelve inches or more, depending upon the size of the coil. The circuit from the street is sent through a suitable, resistance, so that the current will not be too strong. It then proceeds through an interrupter into the primary portion of the induction coil. This primary is composed of rather large wire, of a variable number of turns, depending upon the size of the induction coil. In the center of this primary are a great number of straight iron wires, all cemented together into a cylinder. The secondary coil is composed of a great number of turns of very fine wire, the full length of the wire being many thousands of feet. All these turns, have to be very carefully insulated from each other so that the spark cannot leap from one wire to the other, thus short-circuiting the machine, None of the currents from the street gets into the secondary wire, because the latter is entirely insulated from the primary, but when the current in the primary is broken a current of very high voltage is generated in the secondary coil. It is this high voltage current which is carried by connective wires through the Crookes tube and energizes this and thus produces the X-ray.

A great improvement of coils was achieved when the rotary mercury-spray interrupter was invented. The voltage current passes through this instrument along a spray of mercury, and is thus very rapidly interrupted.

Another style of interrupter, called the electrolytic, is one of the most successful of the devices invented in this connection. The interrupter consists of a glass jar about half full of diluted sulphuric acid. The positive pole of the street current is connected with a German silver wire, which drips down into the liquid within the glass tube, as seen in the cut. The wire rests upon a small procelain cup in the negative end of the cell. The negative pole is a rod of lead shaped like the letter "L". The current on passing through the sulphuric acid, is interrupted by the formation of small bubbles of gas, and this interruption, which is very rapid, produces a very high voltage current in the secondary portion of the induction coil. This is the only interrupter which can be used on an alternating current, and is therefore of great service where only this current is available.

Another great improvement was required in Crookes tubes before the medical profession could use the X-ray to advantage. The early tubes would stand very little current, because the terminals were not strong enough to withstand the immense heat effects of the cathode ray.

As shown in a diagram of the inventor the cathode terminal is concave (hollowed), while the positive is a double terminal shaped like disk. The one near the center of the tube receives the bombardment of the cathode rays. These rays are sent out from the negative whenever the tube is in action, and because the cathode is concave, they are brought to focus at one point, at which point is placed the anode. The theory is now pretty well established that the X-rays are produced by the sudden stopping of the cathode rays at the anode. The X-rays are therefore produced at this point of bombardment, and they spread out, passing through the walls of the tube into the room. They are themselves entirely invisible, but they have the property of making a few chemicals give out light in a very remarkable manner. The most approved chemical is the double salt, platino-cyanide of barium, which is spread upon a cloth in a pulverized condition.

By courtesy of W. Scheidel & co., Chicago Bullet, as detected by the X-Ray.

It was early discovered that the X-rays could penetrate light proof paper and fog a photographic plate. If the hand is placed so that the X-rays can pass through it before reaching the plate, the bones will obstruct the rays more than the plate, and that part of the plate beneath the bones will be less affected than the part next to the tissue. Thus by proper development of the plate an image of the bones of the hand will be seen. The same holds good for all other parts of the body. The usual method is to place the patient on a suitable table in a reclining position. The tube is so arranged that the rays will pass downward through the body of the patient. A photographic plate is then placed beneath that part which is to be photographed. With the earlier apparatus, a long exposure was required to take even a hand, but now very short exposures of the thickest parts of the body will be sufficient. The X-rays are used by the surgeon in detecting any fracture of the bones, dislocation of the joints, or the presence of a foreign body. Formerly, it was a difficult operation to probe for a bullet, but now the projectile can be exactly located with the X-ray. Swallowed coins and pins, often a source of the greatest anxiety to parents, need not be so much feared. A metal object is readily located in any part of the child's alimentary canal, and its progress can be kept track of as it moves through the system. Many deformities seen in the arm and wrist due to incorrect reduction of a fracture are now without excuse, because the X-ray will show wherever a bone is misplaced.

But, of even greater interest is the use of the X-ray in the treatment of certain diseases. The X-ray cannot be expected to cure all diseases, and it certainly should never be tried excepting by those who have bad experience in its use, but the number of diseases in which benefit has been derived from its use is constantly increasing. In no disease has it been more successful than in the treatment of Lupus. This is a disease often affecting the face, producing a hideous raw surface on the cheek, and looking something like an ulcer, but only affecting the outer skin. Hundreds of such cases involving other parts of the body, as well as the face, have already been reported cured. Another disease which is justly dreaded is cancer. This is not a simple disease, but has many varieties, some of which have yielded remarkably to the X-ray treatment, while in others the treatment has produced little effect. "Smokers' Cancer" has yielded very well to the X-ray, and it is an interesting question whether the X-ray might not have prolonged the life of General Grant, had it been discovered and applied early in the progress of the disease. It has been applied to tumors in different parts of the body, and to swollen glands, but the treatment should always be under the direction of a competent surgeon, because in too many cases only an early operation will eradicate the dreaded growths. Rheumatism and cases of facial neuralgia have been benefitted by the rays.

The most powerful X-ray tubes have been recently patented by R. Friedlander & Co., of Chicago. These tubes have the most powerful anodes, so that very strong currents can be sent through them without destroying them. The quantity of the X-rays produced therefore is remarkably increased. Another point of importance is the vacuum of the tube. The earliest tubes were non-adjustable in vacuum, and therefore only one kind of X-ray could be generated. In these improved tubes, however, the vacuum can be perfectly regulated, and as the kind of the X-ray depends upon this vacuum, the operator has at his disposal a great variety of rays.

In the early stages of this new science, newspapers contained accounts of severe X-ray burns, and some of these accounts were not very much exaggerated, but as X-ray photographs are now taken with shorter exposures, this danger is overcome.

A new danger, however, has appeared which affects more particularly the operator than the patient. It has been found that continued exposures to the X-ray will produce a thickening and crusting of the skin which becomes at last very alarming. The finger nails are sloughed off, and large cracks in the skin will develop. When the patient is being treated continuously for a cancer or some other disease, the surrounding tissue must be protected from the X-ray. It is then necessary to use a screen, which will protect both the operator and the patient. A very successful shield just placed on the market is an invention which has suitable openings to allow any amount of the rays desired to come out of the tube, according to the different sizes of the openings. The rays can be projected into the mouth in treating a cancer of the tongue, or the back part of the mouth, while the patient's face is successfully shielded. A great number of other skin diseases have been successfully treated; even superfluous hair has been removed and pustules have yielded to the treatment..

It is thus apparent how a purely scientific discovery has led to important advancements in several different lines of industry, and has been utilized in medicine in the treatment of numerous diseases which had been pronounced incurable.

NEW WONDERS OF THE ELECTRICAL WORLD
MESSAGES WITHOUT WIRES
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© 1998, 2002 by Lynn Waterman