Every-day Science: Volume VII. The Conquest of Time and Space

d the imagination of every beholder, and-next morning-as reported by the newspapers, aroused the amazed interest of the world. This invention c

urity; a car that shows many strange properties, seeming to defy not gravitation alone but the simplest laws of m

ous creature-you feel that it must be endowed with life-

ipe or of a cable of wire-is curved, even very sharply, the car follows the curve without difficulty, and, in defiance of ordinary laws of

ised and stood perfectly still on its tight-rope, as no Blondin could ever do. As stably poised it stood there as if it had two rails beneath it instead of a

all fly-wheels, in closed cases, revolving in opposite directions, each propelled by an electric motor. These are the wonder-workers. They constitute the two-lobed brain or, if you prefer, the double-chamb

g about its axis, is a gyroscope. You can make a gyroscope of your own body if you choose to whirl about, like a ballet-dancer. In a word, the gyroscope is the most common thing imaginable. Indeed, if I wished to startle the reader with a seeming paradox, I might say without transcending t

C ACTION

t could make the hoop go fastest. The hoop itself might be merely a wheel of wire, which would fall over instantly if not in motion; but if given a push it assumed an upright position and maintained it with security, so long as it was impelled forward. It seemed able, so long as it whirled about, to defy the ordinary laws of gravity. A bicycle in motion gives an even more striking illustration of the sa

a fixed direction, and resents-if I may be permitted to use this expressive word-having that direction changed. The same principle is illustrated on a stupendous scale by our revolving earth, which maintains the same tilt year

rection in which its axle points, the mere translation of the body itself through space in any directi

n spinning than when at rest, provided you do not attempt to tip it from its plane of rotation, but that if you do attempt so to tip it, the wheel seems positively to resist, exerting a force of which it did not show a trace when at rest. A

remain at rest until some force is applied to it; nor why when a body is once in motion it tends always to move on at the same rate of speed until some counter-force stops it. Such are the observed facts; they are facts that

tuated by the fact that its whirling particles all tend at successive instants to fly in different directions under stress of centrifugal force. At

he harder the multitude pulled, so long as they remained evenly distributed about the circle, the more rigid the pole would become. But if, on the other hand, all the men were to stop pulling and slacken the ropes, the pole would at once fall over. The pole, und

very important additional principles involved that I shall refer to in a moment, but first let us glance at the car itself and see how the gyroscopes are arranged. We shall find them fastened within the frame-work of the car, at its longitudinal centre, in such a way that their axles are parallel to the axles of the ordin

RANSPORTATION-THE DE WITT CL

iews of which are given, is the working model of a single-rail vehicle exhibited in England by Mr. Louis Brennan in 1907. It is balanced by

NNAN'S

alance a car six feet in length, but it must be understood that these small gyroscopes whirl at the rate of about seven thousand revolutions per minute, and, of course, the gyroscopic force is proportionate to the rate of revolu

man has thus far been privileged to make. The car has shown that it can go up or down a sharp incline; but this, as a moment's reflection will show, does not involve any change of direction of the

, as Mr. Brennan links them, so that any lateral change in the axis of one is balanced by an opposite change of the axis of the other. With

hile passing about a curve, we must investigate more fully the action of the individual gyroscopes. I have already said t

ated. It is this: in order that the gyroscope may exercise its fundamental property of holding its axis fixed, it must have that axis so adjusted that it is free to oscillate or wabble. That sounds distinctly paradoxical, but it is a very essential fact. If Mr. Brennan

st calls "precession." A freely spinning top, if in equilibrium, has no inherency to rise up against gravitation, as your top may have led you to suppose. Your top rises because it is not spinning freely in equilibrium, its action being interfered with by the friction of the

ENNAN GYRO

may understand the action of one of the most remarkable and ingenious of inventions. Figure 1 represents a kind of top called a Foucault gyrostat. It is merely a top or gyroscope in gimbal frames, such as I have already referred to. With certain slight modifications, the diagram that represents it might also be a diagram of one of the gyroscopes in Mr. Brennan's car. Ind

g.

outer frame B D C E is pivoted on the axis D E. Thus the apparatus as a whole is capable of revolving on each of its three principal axes. But under ordinary conditions it is only the inner wheel that is spinning.

its resistance will be shown in a very peculiar way-whereby hangs our tale. If you apply a steady downward pressure to the frame B A C at point A, attempting thus to deflect the axis of the spinning wheel of the gyroscope, the frame will not tip down as you ex

and its meaning, for we

at direction and the point A will begin to rise instead, the frame B A C rotating on its axis B C. This rise of the axis O A will take place even though the downward pressure is continued. You have disturbed the equ

corner, as it were, by the whirling disc, and made to act at right angles to the direction of its application. This change of direction of a force applied is strictly comparable to the change effected by the fa

alled "precession") to the left, and pushing up at A, motion to the right; and that in order to make A either rise or fall, you must "accelerate precession" by pushing to the left or to the right, respectively. But you must understand further, that when, through the application of any of these disturbing forces, you have forced the axis O A int

eir wheels revolving in opposite directions and their outer frames so linked together that when one turns in one direction on its axis D E, the other must turn in the opposite direction.

he framework of the car on the axis D E. If you examine it you will see that it is essentially the

n contact under certain circumstances with the curved segment marked G1, G2, G3, G4, which are strong segments of the car-frame itself-the segments, indeed, upon which the force of the gyroscope is expended in holding the car in equilibrium. It must be understood further that the roller R1 is loosely fitted to the spindle O F and hence can whirl with it when pressed against the segment G1 or G3; whereas the roller R2

g.

long the track, because friction with the spindle causes it to revolve. But this, it will be evident, is equivalent to pushing the spindle F (or the frame A) toward B-"accelerating the prec

e upward, but off to the right toward C; and so, a moment later still the roller R2 will pass beyond the end of the segment G2 and the roller R1 will come in contact with the segment G3, along which it will tend to roll, thus accelerating the precession to the rig

rds, the gyroscope, when its balance is disturbed by a thrust due to any unbalancing of the car, will begin to wabble and continue to wabble until

over the rail, and in that event the axis of the gyroscope will be no longer horizontal. But that is quite immaterial. There is no more merit in the horizontal position than in any other, as regards the tendency to kee

wo rollers R1 and R2 are never in action at the same time, and that it is only the roller R1 that give

does not explain, but the mechanism by which the different segments of the car are made to push against the spindle, and so force it to balance the car in order that it may maintain its own balance, is exceedingly ingenious. Mr.

e force brought to bear on the roller R1 by the segment of the car that strikes against it, the stronger its precession, and hence the more powerful its lift. The oscillations and counter-oscillations thus brought about continue to operate powerfully on the roller R1 so long as the weight of the car is out of balance; and balance is restored only when the heavier side of the car rises, br

about, the axis O A would of course maintain a fixed direction so long as the gyrostat was free to revolve on the axis D E. But if you prevented such revolution, as by clutching the spindle E firmly, and then whirled the gyrostat about at arm's length, the axis O A would at once be forced to take an upright position. If

nd to make the car tip in opposite directions, according to whether the car is going forward or backward, and the tip might be dangerous in going about a curve, as Mr. Brennan found to his cost in his earlier experiments. But when the two gyroscopes, revolving in opposite directions, are linked together, the action of on

tire force of gravity brought to bear on the car. They do not in any sense lift the car; they only balance its two sides, which when left to themselves are approximately of equal weight. The car, as a whole, weighs down on the track just as heavily with the gyroscopes in action as

UTION OF

ears of his early manhood. Observation of the condition of the roads in Australia, and of the enormous retardation of development due to inadequate transportation facilities led him to ponder over the possibilities of improvement in this direction, as he was jolted about the country in a coach with leather straps in lieu of springs. It became clear to him that a way mu

sing the gyroscope, and even purchased several elaborate gyrostats in order to study gyroscopic action. As a friend of Sir Henry Bessemer, he knew of that gentleman's experiments with the gyroscope in attempting to make a steady room in a ship, but these also availe

eting his experiments, Mr. Brennan received a grant of $30,000 from the India Society. He believed that a car one hundred feet long and sixteen feet wide would be balanced

carrying forty or fifty passengers, operated exactly as its inventor had foretold, and the doubts of the most skeptical were set at rest. Photographs of the car in actual operation, with its load

ical moment, as, for instance, when the car is just crossing a gorge or river on a cable? Mr. Brennan's ingenuity has anticipated this emergency. The gyroscopes that balance his cars operate in a vacuum, and all the bearings are so well devised as to give very little friction. The wheels will continue runni

ess running of the gyroscope. All in all, it would appear that the dangers of travel in a gyrocar should be fewer than those that attend an ordinary double-track car; and Mr.

LOUIS BRENNAN'S M

cab-like anterior portion. The platform of the car maintains its equilibrium even