Astounding Stories of Super-Science, October, 1930 Part 48

"They never do," answered the other over his shoulder. "I'll bet that's him down there on the next floor."

The two searchers had emerged upon a wide gallery that commanded a clear view of the main entrance where various specimens of American fauna were mounted in intriguing replicas of their native habitat.

The guard pointed an accusing finger at one of these groups and sprang toward the stairs.

The old gentleman's breath and strength were gone. He could only gaze in the direction that had been indicated by the madly running guard; but he had no doubts. A small boy was certainly digging vigorously at the head of a specimen of _Ursus Polaris_ that the curator had represented in the dramatic pose of killing a seal. A protesting wail arose from below as the young naturalist was withdrawn from his field by a capable hand on the slack of his trousers. And presently, chagrined with failure, the culprit was before his grandsire.

"Gee!" he complained, "I was only looking at the polar bear. Are polar bears always white? Are--"

"You'd better take him away, sir," interrupted the sergeant. "He was trying to pry out one of the bear's eyes with the stick of the lollypop I give him. Take him."

The old gentleman extended both hands. His left found a grip in his grandson's coat collar; his right, partly concealing a government engraving, met the guard's with a clasp of grat.i.tude.

"Sergeant," he remarked in a voice tense with feeling, "a half-hour ago I expressed some ridiculous regrets that Drayle's invention had been kept from the world. Now I realize its horrid menace. I shudder to think it might have been responsible for two like him!"

The object of disapproval was shaken indicatively.

"Guard the secret well, Sergeant! Guard it well! The world's peace depends upon you!" The old gentleman's words trembled with conviction.

Then alternately shaking his head and his grandson he marched down the hallway, ebony cane tapping angrily upon the stone.

As the exhausted but happy warrior retraced his steps a high-pitched voice floated after him.

"Grandpa, are polar bears _always_ white?"

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_The Invisible X-Flyers_

The following is a semi-technical description of the operation of the invisible X-flyers used in "Jetta of the Lowlands" as compiled by Philip Grant in the year 2021 from official records of the Anti-War Department of the United States of North America, and discovered recently by Ray c.u.mmings.

The attainment of mechanical invisibility reached a state of perfection in the year 2000 sufficient to make it practical for many uses. For a century this result had been sought. It came, about the year 2000, not as a single startling discovery, but as the culmination of the patient labor of many men during many years. The popular mind has always considered that science advances by a series of "great scientific discoveries"; "unprecedented"; "revolutionary."

That is not so. Each step in the progress of scientific achievement is built most carefully upon the one beneath it.

And generally the "revolutionary, unprecedented discovery"

has very little of itself that is new; rather it is a new combination of older, perhaps seemingly impractical knowledge. Every scientific theory, every device, is the offspring from a large and varied family tree of many scientific ancestors, each of whom in his day was a remarkable personage.

Thus it is, with the principles of mechanical invisibility.

I deal here with the famous X-flyers. The operation of the plane itself is immaterial; its motors; its wing-spread surfaces; its aerial controls. I am concerned only with the scientific principles underlying its power of invisibility.

Three scientific factors are involved: First, the process known as de-electroniration; second, the theories of color absorption; third, the material, inevitable deflection (bending) of light rays when pa.s.sing through a magnetic field.

I take each of the three in order. The forerunners of de-electroniration were the Martel effects--the experiments of Charles Martel, in Paris, in 1937. A new electric current, of a different character--now called the oscillating current as distinct from the alternating and direct--was developed. Metallic plates were electro-magnetized to produce an enveloping magnetic field of somewhat a different character from any field formerly known.

Dr. Norton Grenfell followed this in 1946 by using the Martel oscillating current to obtain a reverse effect. A similar disturbance of electrode balance. But not a surcharge. An exhaustion. An anti-electrical state, instead of a state of magnetism. A metallic ma.s.s so treated--and with a constant flow of oscillating current holding its subnormal electronic balance--was then said to be de-electronired.

Scientific "discoveries" are largely made by the trial and error system. The scientist takes what he finds. Generally he does not know, at first, what it means. Martell took his oscillating current and "discovered" the Martel Magnetic Levitation, whereby gravity was lessened, and then completely nullified. Grenfell, with his de-electroniration, increased the power of gravity. The two were combined by Grenfell and his a.s.sociates--and the secret of interplanetary flight was at hand.

But there was a host of other workers not interested in s.p.a.ce flyers; they probed in other directions. It was found that the subnormal magnetic field surrounding a metallic substance in a state of de-electroniration had two unusual properties: its color absorption was high; and it bent light rays from their normal straight path into a curve abnormally great. Yet, though it absorbed the color of the rays emanating from the de-electronired metal (the metal itself increasing this result), the magnetic field, while bending the rays pa.s.sing through it from distant objects behind it, nevertheless left their color and all their inherent properties unchanged.

The principles of color absorption are these:--a pigment--a paint, a dye, if you will--is "red" because it absorbs from the light rays of the sun all the other colors and leaves only red to be reflected from it to the eye. Or "violet"

because all the rest are absorbed, and the violet is reflected. Or "black" because all are absorbed; and "white"

the reverse, all blended and reflected. Color is dependent upon vibratory motion. The solar spectrum--its range of visibility through the primary colors from red to violet--can be likened to a range of radio wave-lengths; vibration frequencies; and when we eliminate them all save the "violet"--that is what we have left, in the radio to hear, in color absorption to see.

Thus, a de-electronired metal was found to produce black.

Not black as habitually we meet it--a "s.h.i.+ny" black, a "dull" black; but a true black--a real absence of light-ray reflection--a "nothingness to see"; in effect, an invisibility.

A word of explanation is necessary regarding the other property of the de-electronired field--the bending of distant light rays into a curve, yet leaving their spectrum unchanged. It was Albert Einstein who first made the statement--in the years following the turn of the century at 1900--that it was a normal, natural thing for a ray of light to be slightly deflected from its straight path when pa.s.sing through a magnetic field. The claim caused world-wide interest, for upon its truth or falsity the whole fabric of the Einstein Theory of Relativity was woven.

An eclipse of the sun in the 1920's established that light is actually bent in the manner Einstein had calculated. A magnetic field surrounds the sun. In those days they did not know that it is a field of subnormal electronic balance--in effect, the result of de-electroniration. It was found, nevertheless, that stars close to the limb of the sun appeared, not in their true positions, but s.h.i.+fted in just the directions and with the amount of s.h.i.+ft Einstein predicted. The light rays coming from them to the eye of the observer on Earth were curved in pa.s.sing so close to the sun. But the color-bands of their spectrums were unaltered.

And some of the stars actually were behind the sun, yet because of the curved path of the light, were visible. I mention this because it is an important aspect of the subject of mechanical invisibility.

With the foregoing factors, the secret of mechanical invisibility is constructed. Gracely, an American--following a long series of world-wide experiments, tests of current strength, frequencies of oscillation, suitable metals, etc., which I cannot detail here--in 1955 was the final developer of the mechanisms subsequently used in the X-flyers.

Gracely produced what he christened "aluminoid-spectrite"--a light-weight alloy which, when carrying an oscillating electronic current of the proper frequency, produced the effects I have described. It absorbed from the light rays coming from the metal, all the colors of the solar spectrum, well beyond the range of the human eye at both ends of the scale. The result was a "visible nothingness."

A moment's thought will make clear that term. A visible nothingness is not invisibility. The fact that something was there but could not be seen was obvious. A black hat with a light on it and placed against an average background is almost as easy to see as a white hat. Gracely's first crude experiments were made with an aluminoid-spectrite cube--a small brick a foot in each dimension. The cube glowed, turned, dark, then black, then was gone. He had it resting on a white table, with a white background. And the fact that the cube was still there, was perfectly obvious. It was as though a hole of nothingness were set against the white table. It outlined the cube; reconstructed it so that for practical purposes the eye saw not a white, aluminoid brick, but a dead black one.

And this is very much what a man sees when he stares at his black hat on a table. The hat occults its background, and thus reconstructs itself.

But when Gracely determined the proper vibrations of his oscillating current to coincide with all the other material factors he was using, the final result was before him-real invisibility. He used a patterned background--a symmetrically checkered surface, most difficult of all. The light rays coming from this background pa.s.sed through the magnetic field surrounding the invisible colorless cube, and were bent into a curved path. But their own color-spectrum--in actuality the color, shape, all the visible characteristics of the background--was not greatly altered. The observer saw what actually was behind the invisible cube: the checkered background, sometimes slightly distorted, but nevertheless sufficiently clear for its abnormality to escape notice. Thus the cube's outlines were not reconstructed; and, in effect, it had vanished.

In practical workings with the X-flyers, no such difficult test as Gracely's cube and rectangular, symmetrically patterned background is ever met. The varying background behind a plane--at rest or flying, and particularly at night--demands less perfection of background than Gracely's laboratory conditions. I am informed that an X-flyer can vaguely be seen--or sensed, rather--from some angles and under certain and unfavorable conditions of light, and depending on its line of movement relative to the angle of observation, and the type and color-lighting of its background. But under most conditions it represents a very nearly perfect mechanical invisibility.

There is one aspect of the subject with which I may close this brief paper. I give it without technical explanation; it seems to me an amusing angle.

The theory of stereoscopics--the vision of the twin lenses of the human eyes, set a distance apart to give the perception of depth, of the third dimension--is in itself a subject tremendously interesting, and worthy of anyone's study. I have no s.p.a.ce for it here, nor would it be strictly relevant. I need only state that a two-eyed man sees partially around an object (by virtue of the different angles from which each of his eyes gaze at it) and thus sees a trifle more of the background than would otherwise be the case. And this--these two viewpoints blended in his brain--gives him his perception of "depth," of "solidity"--the difference between a real scene of three dimensions and a painted scene on a canvas of two dimensions with only the artist's skill in perspective to simulate the third.

And I cannot refrain from mentioning that in Government tests of the Anti-War Department to determine the perfection of the invisibility of the X-flyers, it was a one-eyed man who proved that they were not always totally invisible!--Ray c.u.mmings.

_Thank You_