Toying with Tai Chi

by Christopher Dow

 

The movements of Tai Chi Chuan can be difficult to learn, but once you do, they seem perfectly natural as you flow through the form. In fact, being relaxed and natural are the name of the game in Tai Chi, otherwise, playing Tai Chi becomes a chore rather than a relief, and the practice becomes less effective for both health and self-defense. That doesn’t mean that Tai Chi should be easy or rote or effortless. It’s still work, but work of the sort that elevates rather than crushes. In that respect it has much in common with play. Indeed, practicing Tai Chi often is called "playing Tai Chi."

 

Children at play instinctively understand that their play is in deadly earnest as long as it remains unattached to outcome. This allows their actions to have meaning without negatively impacting their lives after play. I can be the nasty bad guy in play, but afterwards, I revert to my usual, less bad self. In this essay, though, I’m not going to digress further into play as a topic; instead, I’m going to look with Tai Chi eyes at some of the objects that children and adults play with and how they illustrate Tai Chi principles.

Tops and Gyroscopes

 

One of the first Tai Chi metaphors I ever heard was a comparison of the Tai Chi Chuanist with a spinning top. There are four basic types of tops: hand-thrown, spindles, device activated, and mechanical. (Figure 1) Each type is spun in a different manner, but no matter how a top is fashioned or how it begins spinning, the result is the same: It spins around its axis until friction consumes enough energy for the top to wobble then fall over.

 

But while a top is spinning, if an object, say a penny, is tossed at it, the top’s spin both diverts and repels the object in the same instant. In part, this occurs because, in the moment that the penny strikes, the spin moves it laterally away from the body of the top, and then that same spin, now lateral for a split instant to the penny’s tangent, propels the penny away. But the spin is possible only because the top, when spinning, rotates around an axis. In other words, it embodies Central Equilibrium. Without Central Equilibrium, the energy that can cause spin will only cause uncontrolled tumbling.

 

Central Equilibrium does not exist in an inert top, even though the object does have one major potential axis and a great, almost infinite, number of other potential axes. It is the rotational movement of the top’s mass around one of these axes that generates Central Equilibrium. Central Equilibrium, in other words, does not exist in a body at rest. Without Central Equilibrium, there is no spin, and spin cannot exist without generating a Central Equilibrium.

 

The idea in Tai Chi is to refine the diameter of Central Equilibrium to an infinitely small axis, around which perfect balance exists. Of course, a Tai Chi Chuanist does not literally spin like a top, but the exponent is trained to rapidly rotate around his or her axis in short to longer arcs, using particular arm and hand movements to engage with, stick to, and control the opponent during the course of the rotation. 

Top A.jpg

Figure 1 Four types of tops, clockwise from top left: hand-thrown, spindle, device activated, and mechanical. (1)

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Interestingly enough, the stability—call it rootedness—of the top while spinning around its Central Equilibrium also is an equal factor in the top’s ability to repel a penny. While a top is spinning, it is impossible to touch its Central Equilibrium because the body of top will repel any touch. Okay, maybe not always, you say. You can toss an anvil on the top and crush it, proving me wrong. But am I wrong? The anvil is massive enough to halt the top’s spin in the instant before it crushes the top. So, the spin still has to be halted in order to touch the top’s Central Equilibrium, in which case, the Central Equilibrium still is lost and no longer there to be touched.

 

But I digress, and dropping an anvil onto a top is tantamount to throwing a fully-loaded eighteen-wheeler onto a Tai Chi player. In practical terms, if you nudge a top, your finger will be deflected, and the top might creep backward a bit, but it will remain in a relatively upright orientation. Indeed, you will feel a return pressure if you nudge it. The rootedness of a spinning top might be related to the fact that it is completely single-weighted—its balance is almost absolutely singular. Tai Chi players know that real power is generated from single-weightedness in the body, which allows not only for stability but for full expression of power by combining physical movement with a surge of internal energy, both along a single path.

Gyroscopes take the ideas of Central Equilibrium and single-weightedness a step farther. (Figure 2) Once you set a gyroscope spinning, the entire device will writhe and twist like a living body when you pick it up and handle it. Because of the flywheel-like spin of the rotor, a gyroscope has almost exactly the same weight at every degree of its circumference. And because of this absolute equilibrium throughout the body of the gyroscope—rotor, gimbal, and frame—all the weight of the gyroscope is focused down into its single foot. Remarkably, you can lay a spinning gyroscope almost onto its side, with only its foot touching a pedestal or table edge, and it will seemingly float there, sideways, in apparent contravention of the pull of gravity. Since all the forces of the gyroscope are directed down into the foot, even a canted gyroscope has a Central Equilibrium that roots itself directly to Earth’s gravity at the central point of its foot. (2)

 

In fact, a spinning gyroscope can give a good sense of how rootedness can develop natural resistance—by this I mean internal energy rather than strength—against outside force. Set a gyroscope spinning, place it on its foot, and try giving it a gentle shove from the side with your finger. You’ll feel pressure pushing back, even though the gyroscope has neither muscle, motors, nor intent.

 

Drum Monkey

 

Another amusing toy that is similar in its reliance on Central Equilibrium is what I used to call a twizzle drum until I learned the term “drum monkey,” which is much more colorful. (Figure 3) It’s also more commonly called a hand drum, though lots of small drums that are struck with the hands, such as bongos and tambourines, also are called hand drums.

 

Apparently the drum monkey has no specific origin since it can be found in Asian, African, and Native American cultures. The real use of drum monkeys is ceremonial, though most people think of them as novelty toys. But their import for Tai Chi can be seen during the climactic fight in Karate Kid II when the villagers twizzle drum monkeys to encourage Ralph Macchio’s character to go with the flow so he can defeat his opponent.

 

When you look at the action of a drum monkey, it’s easy to see the message Macchio’s cheerleaders were sending: Loosen and relax your shoulders, and let the twisting of the body around Central Equilibrium (the handle) naturally rotate the drum (the torso), powering the arms and fists (the strings with the beads attached to their ends) in the appropriate directions. After all, a drum monkey has absolutely no strength in its arms, yet the rotation of its body around Central Equilibrium causes the strings and terminal beads to whip quite furiously back and forth against the drum heads. In Tai Chi, one simply uses the legs to powerfully twist the waist, whipping the upper body, which is controlled through refinements of the arm and hand movements to produce desired martial effects.

Rubber Bands

 

Rubber bands might be the only “toy” that can be found in every office. You can stretch them, shoot them, cat’s-cradle them, and twist them. Not only are they fun, they are instructive for Tai Chi.

 

The way that a twisted rubber band can store energy then release it is amply demonstrated by rubber-band airplanes: those balsa wood toy fliers with red plastic propellers and tiny wheels mounted on springy wires. Twist the propeller for a large number of turns, then let the plane go, and the uncoiling energy of the rubber band spins the prop, which pulls the plane through the air.

 

Tai Chi, too, relies on twisting movements to coil energy that then uncoils into, against, or away from an opponent. The main difference is that the rubber band in the airplane is twisted for a large number of turns, while the Tai Chi Chuanist only twists part way around. But the elastic bands of the human body—known as ligaments, tendons, and fascia—are considerably more powerful than the rubber band in a toy airplane, and the latter two are connected to major muscles and muscle groups. Even a partial twist and recoil of the body, appropriately applied and augmented by proper muscular action, is powerful enough to send the opponent flying. Interestingly, the uncoiling often is accompanied by a corkscrewing movement of a limb—usually an arm—that aids in expressing the power of the uncoiling, just as the uncoiling of the rubber band in the airplane activates the corkscrew of the propeller, which is what actually manifests the energy from the coiled rubberband. (See Natural Patterns for a discussion of spirals and corkscrewing action.)

 

Rubber bands can be stretched and released as well as twisted. Who among us hasn’t shot a rubber band across the room—probably at somebody? In a very similar way, the Tai Chi player can stretch or compress tendons and fascia, loading them with elastic energy that can be suddenly released against or away from an opponent. Often the energy that is loaded comes from the opponent’s own force, which then, in that mysterious interface that exists between yin and yang, is transformed into the exponent’s power. Depending on the method of release, the resulting surge of energy can be controlled as a dull wave front that can surgingly expel an opponent, or as a sharp jolt that will penetrate his body.

 

I have employed a large rubber band in my classes as a teaching tool. It’s a big one that I found at Office Depot, and the darn thing cost about $7! (Figure 5) You also could also use a bungee cord whose ends have been hooked and duct-taped together. I have the student loop the band around both wrists, for example, and do split movements such as Slant Flying or Single Whip, telling them to feel the growing tension and to control it not through the band but through their shoulders and back. In essence, the rubber band amplifies the elastic stretch and release of the tendons and fascia and gives even a novice a tangible sensation of stretching out and then releasing the stretch instead of simply moving the limbs without internal energy. In effect, the rubber band gives a dynamic sensation of using the elastic power of the Tai Chi Bow. In some split movements, the stretch can be released to effect from either end (Slant Flying, for example), while in others, the release is primarily unidirectional (Single Whip, for example).

I've also seen one prominent Tai Chi teacher employ a rubber band as a teaching device. He has his students string the band around their legs at knee height. The band is of a size that will tighten as the student stretches into Bow Stance. This would give the novice student the tangible sensation of having to press the knees slightly outward to increase stability and rooting.

 

Magnets

 

Magnets are everywhere, from toy horseshoe magnets to the sun and other celestial bodies. They’re found in motors, generators, loudspeakers, electric guitar pickups, computer drives, compasses, and the rubber seal around your refrigerator door—and in the kitschy kitchen magnets you’ve stuck on the outside of that door. Every electrical wire and device is surrounded by an electromagnetic field, we live totally immersed in the magnetic field generated by Earth, and each of us generates our own magnetic field, albeit a weak one. Magnets are ubiquitous, and they are quite useful as well as being quite natural. Even alone, they make interesting toys as evidenced by the horseshoe magnets you can find in a large number of toy boxes. In fact, electromagnetism is one of the four fundamental forces of nature, along with the strong nuclear force, the weak nuclear force, and gravity. (Many physicists now do not consider gravity to be a fundamental force, but simply the effect of mass warping space-time. Okay. But if I stumble, gravity, whatever it is, will instantly take over and whop me with that mass.)

 

Most of us know that a magnet generates a field of force called a magnetic field around itself and that it has two poles: positive and negative. (Figure 6) There, in a nutshell, is the yin and yang of it. The force of the magnetic field emerges from the positive pole, cycles through the space around the magnet in a toroidal pattern, and reenters the magnet at the negative pole. Magnetic fields do not have boundaries and theoretically extend infinitely outward, though in practical terms, the effects diminish greatly with distance. Also, magnetic fields will pass unimpeded or with only minor diminishment through many—but not all—forms of matter, so they’re kind of supernatural in that regard.

 

The Eurocentric view of Earth orients the negative pole of planet Earth at the top and the positive pole at the bottom. This is undoubtedly an artifact of the age of European exploration, when the compass was the mariner's major guiding tool. The magnetized needle of a compass points north because the positively charged end of the needle e charge is attracted to the Earth's negative pole, and the Earth's magnetic polarity was not understood at the time. Had it been, we might be adhering to the ancient Chinese view, which was just the opposite and orients the globe with the South Pole at the top. It is probably a more accurate view if we consider the fountaining of energy to go upward and the reabsorption of it to come in from the bottom, as occurs with any magnet, including the human body.

 

However you look at it, the polarity of magnets demonstrates the yin and yang of things through magnetic attraction and repulsion. If you bring two magnets together at the opposite poles—negative meeting positive—there will be a mutual attraction. (Figure 7) But if you bring the magnets together at similar poles—negative to negative or positive to positive—the two magnets will push against each other with invisible force. The former could be considered an example of single-weightedness and cooperation, while the last two might be examples of double-weightedness and the attendant confrontation of energies that results. If you cooperate and blend your energies, you and your opponent become one, but if you meet force with force, only struggle results.

 

Many Tai Chi folks know how to play with this repelling force when they roll a ball of chi between their hands. (Figure 8) What is happening here is that positive chi energy—which is, at its base, electromagnetic in nature—is emerging from both palms. When positive meets positive, the result is repulsion, and this can be felt as a tangible force between the two palms. Using rotating movements of the hips and waist to motivate the arms and hands gives this force the character of a ball, and this ball can be “rolled” in front of the body, creating a controlled swirl in the individual’s chi/electromagnetic field. (Figure 9) The rotating of the hips not only causes the rolling action, but it also helps power the energy that creates the ball by sending alternating pulses of chi up the legs as you rotate back and forth, amplifying the chi running down the arms and emerging from the palms. The closer the hands roll and the smaller the ball, the greater the pressure between the palms, and the father apart the hands are and the larger the ball, the less the pressure. Again, the power of a magnetic field diminishes over distance.

Newton’s Cradle

 

Next, we’ll look at Newton’s Cradle, also called Collision Balls and Executive Desk Balls. (Figure 10) The former name comes from it’s creator, Isaac Newton, the middle name is obvious, and the last one comes, presumably, because 1) only executives can afford to waste money on frivolous items that occupy valuable desk space that they’re not using because executives do so little real work, 2) executives have so little to do that they have time to play with such frivolities, 3) executives have so little real creativity that they can easily become mesmerized by a simple mechanical device, 4) executives like to give housekeeping staff difficult objects to dust, or 5) executives perpetually study the middle ball which remains static when two end balls are set in motion, demonstrating the chief tactic of the middleman: Do absolutely nothing but transfer something one way or another and reap profits off the efforts and energy of others.

 

Okay, I’ll stop, though it’s easy to be cynical these days. Back to Newton’s Cradle. This from Wikipedia:

 

Newton’s cradle…is a device that demonstrates conservation of momentum and energy using a series of swinging spheres. When one on the end is lifted and released, it strikes the stationary spheres; a force is transmitted through the stationary spheres and pushes the last one upward…. A typical Newton’s cradle consists of a series of identically sized metal balls suspended in a metal frame so that they are just touching each other at rest. Each ball is attached to the frame by two wires of equal length angled away from each other. This restricts the pendulums’ movements to the same plane.

         If one ball is pulled away and is let to fall, it strikes the first ball in the series and comes to a nearly dead stop. The ball on the opposite side acquires most of the velocity and almost instantly swings in an arc almost as high as the release height of the first ball. [In the absence of friction or other external forces besides gravity, the opposite ball would swing exactly the same height.] This shows that the final ball receives most of the energy and momentum that was in the first ball. The impact produces a compression wave that propagates through the intermediate balls. Any efficiently elastic material such as steel will do this as long as the kinetic energy is temporarily stored as potential energy in the compression of the material rather than being lost as heat.

         With two balls dropped, exactly two balls on the opposite side swing out and back. With three balls dropped, three balls will swing back and forth, with the central ball appearing to swing without interruption. (6)

 

I’ve quoted the Wikipedia entry at length since the presentation was pretty succinct and I’d waste time and clarity paraphrasing it. There’s some fancy mathematics involved in the details of the motions of the balls, such as whether or not the balls at rest actually touch or not and other factors that I don’t dare attempt to go into. But I think at least one Tai Chi lesson is clear from the motion of Newton’s Cradle.

 

Most of us Tai Chi folks have seen, have demonstrated, or been pushed by a trick Tai Chi application. This is when the demonstrator holds a Press posture and has one person push against his raised arm while several other people line up behind, all pushing, too. As they push, the demonstrator gives a pop of peng energy from his Press posture, and all the people who are pushing move slightly backward except for the last person in line, who is jolted back farther, often several feet. Clearly this is the same conservation of momentum and energy shown by Newton’s Cradle.

 

In this demonstration, Peng energy can easily be seen propagating through the line of people and finally manifesting in the last person in line. But the more important propagation is less visible because it happens inside the Tai Chi Chuanist’s body. We often think of bouncing our energy down into our feet then back up through the legs and torso, into the arms and hands. This movement of internal energy, combined with physical compression and release, acts very similarly to the energy system demonstrated by Newton’s Cradle.

Figure 2 A spinning gyroscope exhibits equal weight in all directions lateral to its plane of spin. All the forces are directed into its foot. (3)

Gyroscope.jpg
Drum Monkey-2.jpg

Figure 3 Twizzling the handle of a drum monkey will cause the beads on the ends of the strings to slap against the drum heads even though the strings are completely without energy of their own.

Rubberband Airplane.JPG

Figure 4 Rubber-band balsa airplanes are powered by the twisting of an elastic band that then releases its energy in a coiling movement, driving the plane through the air. (4)

Giant Rubber Band-2.jpg

Figure 5 My large rubber band. The knot in the middle is to shorten the total length of the band. You could use a bungee cord with its ends hooked and taped together.

Magnet 2A.jpg

Figure 6 Magnetism in a bar magnet (top left) is caused by an alignment of the iron molecules in a common direction. Magnetism in Earth (top right) is produced by geodynamic processes. The electromagnetic chi field (right) is generated by bioelectrical energy flowing along the nerves. The fields of all three objects exhibit polarity and extend infinitely in all directions but are most powerful in close proximity to the magnetized object.

Magnet 2B.jpg
Magnet 3.jpg

Figure 7 Magnets exhibit polarity. Positive and negative are attractive to one another, while positive and positive or negative and negative are mutually repelling. (5)

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Figure 8 The Tai Chi sphere can be played at various diameters. The larger the sphere, the more diffuse the sensation between the hands, while smaller manipulations create a greater sensation of heat and density.

Roll the Ball.jpg

Figure 9 The basic Tai Chi manipulation is to roll the Tai Chi sphere from side to side. The spheres with the blank double fish indicate the moment when the energy switches polarity and the ball starts rolling in the opposite direction.

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Figure 10 Various examples of Newton's Cradle. Click any of the images to see the animations. (6)

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At it's base, this demonstration recalls the idea from the Tai Chi Classics that one should learn to “pass a thread through the nine-channel pearl.” Apparently, the nine-channel pearl was a game in which Chinese girls attempted to push a thread through a ball with nine caddywampus holes drilled in it. In Tai Chi, the nine-channel pearl is the human body, the channels are the major joints that must be aligned correctly to give the exponent’s uncoiling force and energy a proper path to follow. The idea is that the Tai Chi Chuanist must learn to push from a single foot and consciously direct the energy sequentially through every joint—ankle, knee, hip, shoulder, elbow, wrist, and the three joints of the phalanges—all the way to the fingertips. When considered like this, Cheng Man-ching advocating the use of Ladylike Wrist during form practice makes perfect sense because that hand form allows the chi to flow unimpeded to the fingertips.

 

Threading the nine-channel pearl can be thought of as an unfolding process or even a pneumatic process in which the body sort of inflates in a wave that progresses from foot to hand, but in a sense, the dynamics also are similar to those of Newton’s Cradle. The joints are like the places where the balls of Newton’s Cradle touch, and the body parts are like the balls themselves. Chi in the foot bounces through the ankle joint to the fibia. Then it bounces through the knee joint to the femur, through the hip joint into the pelvis/torso, through the shoulder joint into the humerus, and so forth down the arm and through the last joints of the fingers.

 

But there is an important difference. In an idealized Newton’s Cradle (without friction), the energy propagates through the several balls then knocks the final ball into the air. This ball then falls back with equal velocity, strikes the first of the lined-up balls, and transmits its energy through the line to the ball on the other end. This one reacts by bouncing into the air exactly as high as its initial fall, and so on, each strike imparting only the energy with which it was endowed. The Tai Chi exponent is not so mechanized. The initial impetus of the energy surge, coming either from the opponent or the exponent himself and going down the leg, terminates at the sole of the foot. Because the surface on which the foot rests is solid, the foot, unlike the end ball, has no space into which it can move.

 

In a way, Earth itself has become the final ball, and clearly Earth is too heavy to move much by pushing your foot down on it. So, instead of swinging out then falling back to retransmit itself back along the path from which it came, the energy instantly rebounds back into the foot. It’s as if the energy takes an almost instantaneous 180° turn inside the Earth, making the foot not just the ball that acts against the ball of the Earth, but also the next ball in line as the energy reemerges into the foot. And because the human body is flexible and mind-directed, the rebounding energy can be tremendously augmented by the strength of the uncoiling leg muscles, tendons, and fascia as it surges up the leg, through the hips and waist, and into the torso.

 

This augmented energy propagates through the intervening body segments (the balls) and arrives at its terminus (hand, say, but it could be an elbow, shoulder, etc.) in a very powerful state because it has built up momentum and power over a distance of about ten feet—through the body, into the ground, then back up through the body—in a very rapid fashion. So, unlike the end balls in Newton’s Cradle, which each receive and transmit exactly the same amount of energy, the end ball in the Tai Chi Chuanist’s train of balls—often the hand—receives a seriously amplified pulse of energy that then acts upon the opponent.

 

In the case of the Tai Chi Peng demonstration describe above, the energy doesn’t go all the way through the arm to the fingertips. Instead, it goes only as far as the demonstrator’s jolting palm, then through the join between the palm and the inside of the demonstrator’s forearm, then through the join between the outside of the demonstrator's forearm and the palms of the first person in the pushing line. Thereafter, each person in line is like a ball that is subsequently jolted through the places where they touch until the jolt terminates, with full force, at the final person in line, who then bounces away.

Maybe we should dub the Peng demonstration outlined above "Chang's Cradle," after Chang San-feng.

Crack the Whip

 

Okay, you don’t need a toy to play Crack the Whip. But it is play, and this particular game amply demonstrates Tai Chi’s whipping power. (Figure 11) It's also kind of the yin to the yang of Newton's Cradle: a stretching, flexible, pulling energy rather than a compressive and concussive energy.

 

For those of you out there who don’t know what Crack the Whip is all about, it’s when a bunch of kids stand in a line in a big field, sequentially holding hands. Then the person at the head of the line begins hauling backwards, dragging the next person along, who drags the next person, and so forth down the line. Pretty soon, the whole train of kids is snaking around across the surface of the field as the head person turns this way and that, sinuously weaving his followers along behind him.

 

The pace and turning of the head might appear leisurely and gradual, but as the snaking effect works its way down the line and becomes more sinuous, the people toward the tail end of the line find themselves whipped back and forth as they run along, dragged by the person in front of them. The last person in the line receives the most violent snaking effect and eventually is “cracked” off the end of the line at the apex of a whipping turn and sent rolling and tumbling across the grass. But even as the last person is cracked off and tumbles, the person at the head of the line—the handle of the whip—continues to maintain a leisurely pace. You can see the same sort of effect in bullwhip, of course, but it’s also present in other scenarios, such as a roller coaster. The people in the front car experience the most stable ride, while the people in the tail car are more violently whipped and thrown around in their seats.

Snap the Whip-Winslow Homer-1.jpg

Figure 11 Snap the Whip by Winslow Homer (1872) (7)

Well, I guess it’s time to stop toying around with these ideas and go play Tai Chi. While I might be tempted to think back to my childhood toy box and the Tai Chi toys it held. Instead, I’ll try to concentrate on my Tai Chi form, which has become the biggest and best toy box I could imagine. It might be finite in external size—bigger than a breadbox and smaller than a room—but the whole of reality seems to be in there. It’s like Felix the Cat’s magic bag of tricks or an infinite store where playthings, tools, and insights line the shelves of secrets I didn’t even know existed. To discover those secrets, all I have to do is start playing.

Notes

1  Top images:

Hand-thrown top: (LINK BROKEN)

http://www.bing.com/images/search?q=Wooden+Toy+Tops&view=detailv2&&id=FD4AA757FB2D0AA43ECD7F79D175DCEB5C1A3481&selectedIndex=135&ccid=uLD86VFT&simid=607994004044646251&thid=OIP.Mb8b0fce95153553df11815079e3b4b76o0&ajaxhist=0

Spindle top: (LINK BROKEN)

http://www.bing.com/images/search?q=Wooden+Toy+Tops&view=detailv2&&id=D064208FFABB9BE924FC09E8EE20AB4DB1D69E6E&selectedIndex=4&ccid=jz%2f2RxMV&simid=608020727328672253&thid=OIP.M8f3ff647131563e57fcd324a91091271o0&ajaxhist=0

Device-activated top: (LINK BROKEN)

http://www.bing.com/images/search?q=Wooden+Toy+Tops&view=detailv2&&id=D622A35DAF092D11091A70C4A60F62F31E366852&selectedIndex=1&ccid=ACV%2fPqE6&simid=607988261665770354&thid=OIP.M00257f3ea13ab1ee3b39f66693b0a3f6H0&ajaxhist=0

Mechanical top: (LINK BROKEN)

http://www.bing.com/images/search?q=Vintage+Spinning+Tops&view=detailv2&&id=AAE5083F9712D223FE0AAC12A39E35E6BE994AF0&selectedIndex=10&ccid=OXKE6Dmr&simid=608031146914873397&thid=OIP.M397284e839ab0fc00d509307c7281044o0&ajaxhist=0

 

2  Wikipedia entry: "Gyroscope"

https://en.wikipedia.org/wiki/Gyroscope

 

3  (LINK BROKEN) https://www.bing.com/images/search?q=gyroscope&view=detailv2&&id=88A50ED5256F4FBC8656013D868BDA5F7A214DB0&selectedIndex=0&ccid=yVWyzwnY&simid=608034514176311815&thid=OIP.Mc955b2cf09d870764fc6432516f3bf5bH0&ajaxhist=0

 

4  ​(LINK BROKEN) http://www.bing.com/images/search?q=Vintage+Spinning+Tops&view=detailv2&&id=AAE5083F9712D223FE0AAC12A39E35E6BE994AF0&selectedIndex=10&ccid=OXKE6Dmr&simid=608031146914873397&thid=OIP.M397284e839ab0fc00d509307c7281044o0&ajaxhist=0

 

5  (LINK BROKEN) http://www.bing.com/images/search?q=Vintage+Spinning+Tops&view=detailv2&&id=AAE5083F9712D223FE0AAC12A39E35E6BE994AF0&selectedIndex=10&ccid=OXKE6Dmr&simid=608031146914873397&thid=OIP.M397284e839ab0fc00d509307c7281044o0&ajaxhist=0

 

6  Wikipedia entry: "Newton’s Cradle"

https://en.wikipedia.org/wiki/Newton%27s_cradle

7  Wikipedia entry: "Snap the Whip"

https://en.wikipedia.org/wiki/Snap_the_Whip

 

Images not otherwise attributed are my own illustrations or photos.