Spouting Bowls!
- Back in stock, despite SOLD OUT due to the worldwide copper
shortage. Giant size - 17 inches across!
I have sold all of these - I don't have any more. Send email if you wish to order one; perhaps I can find one in my attic.
What, you've never heard of a Chinese Spouting Bowl? You mean that you've never seen water dance to vibrations from your hands? Have we got news for you...
Half-fill the copper-bronze bowl with water. Then, rub the two handles with your wet hands.
At first, nothing happens. After a minute, tiny ripples begin to dance on the surface. Suddenly, water droplets spring from the water's surface. Keep rubbing and you'll see a fountain of droplets jumping from four places in the water.
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Acme's Big Spouting Bowl 380 mm diameter About 15 inches across |
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Notice how the water jumps from 4 places around the spouting bowl. |
You can get water to jump over a foot from the surface; with practice you can get droplets to spring two feet high. Spouting Bowl Masters claim to get water leaping a full meter over the bowl, but they're either lying or have short metersticks.
The water springs up from the mouths of four dragons, engraved on the bottom of the bowl.
The bronze foundry which makes these bowls says that these will "impove your Health, stimulate your activity of the mind, increase the central concentration, and maximize all essential muscles. With practice, the sound will be more elegancy."
What really happens? As you rub your hands against the handles, the two handles vibrate. The handles couple the vibrations into the bowl, exciting the bowl to vibrate -- the big bowl sounds a low G (196 Hz) and the medium bowl sounds an E (330Hz). These set up standing waves in the water -- the dancing waves (crispiations) show the pattern of the vibrational nodes. The pattern -- called a Chladni pattern -- can be thought of as an interference pattern. Where the waves reinforce one another, the water droplets jump off the surface.
The water springs up from four areas; the bowl shows a dragon spouting at each of these locations. I suspect that this means the second order vibration. You can do a computerized nodal analysis and publish your results, and become a premier member of the field of Theoretical Chinese Spouting Bowl Physics.
The secret to getting these to work? Wash your hands with soap, then rinse them well, to remove all slippryness. Place the bowl on a soft surface like grass. Keep your hands wet. And rub your hands forwards and backwards on the handles (don't use a circular or sideways motion) It's much like making a wine-glass ring by rubbing your finger around the lip.
The water crispiations and spouts are Faraday waves -- nonlinear standing waves oscillating in the water, excited by the vibrations of the bowl. They are related to the physical phenomena of oscillons and solitons, which are exciting to hydrodynamic physicists ... they love to write differential equations about 'em.
April 2003 - I just discovered that these work great when resting on bubble-wrap. Place a 30cm square (foot-square) of bubblewrap on a tabletop, floor, or concrete walk. Put the half-filled spouting bowl on top of the bubblewrap. The bubblewrap doesn't absorb much of the vibration. No need for a special pad.
AHA- Oct 2010: Brooke Clarke reports great results when you stick 4 sticky pads under the spouting bowl! "The metal bowl will slide on a counter top. Using bubble wrap (my first attempt) did not work well because the bowl still moved. A wet towel might be better but would damp the vibrations. A simple fix is to use "Self Adhesive Anti-Skid Pads" (Shepherd 9970 from Home Depot). Placed at the nodes, i.e. along a line between the center of the two handles and along a line at right angles to that line."
Important - these bowls are made of bronze, an alloy which contains copper. So they are NOT SAFE FOR FOOD. Do NOT use these as punch bowls, salad bowls, or for food preparation. DON'T USE THEM FOR FOOD OR DRINK! Do NOT wash, peel, cube, and boil eight large potatoes, mixing in 1/2 cup Mayo, 4 Hard Boiled Eggs (sliced), 1 Tsp Dijon Mustard, a handful of chopped green onions, some sliced celery, and a dash of garlic powder.
Also - the bronze used in these has a small amount of iron. So if you leave water in them for a long time, a few tiny rust spots may form.. These won't affect the spouting action.
I'm told that if you use ethanol, you can get six jumping points instead of four. A higher order standing wave, eh? [note added Dec 2, 2002 ... I tried this, but could not get *any* spouting action with alcohol. The alcohol made my hands too slippery! Next experiment is to try exciting the modes using an audio oscillator.]
June 3, 2009 - Dr. Steve Dorney of the Institute for Sound and Vibration Research at the University of Southampton has measured these with vibrometers and analyzed them using FFT's. Wonderful work which shows the vibrational modes!
You can own a real giant 17" Chinese Spouting Bowl for only $295 -- less than the price of a superconducting cyclotron!
Years ago, I had three sizes of these Spouting Bowls:Medium (300mm/12inch diameter), Big (380mm/15 inches), and Giant (440mm/18 inch) I now have only sell the giant sized ones, because they're the easiest to spout and don't jiggle around as much.
Put your hands on a Giant Chinese Spouting Bowl. It's 445 mm (17.5 inches) in diameter , and 100mm (5 inches) high. The substantial handles extend another 70mm (3 inches). Same shape as the others, just bigger. Easiest to get to spout, and make the tallest spouts (but still not a meter). Costs more, as giant dragons are scarce nowadays. (no picture yet, but they look pretty much the same as the others)
Because the giant spouting bowls are big, I will ship them using UPS ground. Shipment via Airmail to Europe will cost about USD$50.
Chinese legend tells of the Eight Immortals of the Wine Cup ... Tang Dynasty Poet Li Po drank an entire bowlful of wine, leaned out of his rowboat to embrace the reflection of the moon, and drowned with a wide grin. Is it true? Buy an Acme Spouting Bowl and try it yourself! Incidentally, this is also called a Chinese Singing Bowl, Dancing Water Bowl, Chinese Fish Basin, a spouting dragon bowl, bronze dancing water basin, Singing fountain bowl, Oriental Bronze Spouting Bowl, or a two-handled whatchamacallit.
Two Spouting Bowls - medium and big - along with a big Klein bottle. Colors vary from deep blue-green to light greenish bronze.l