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The Toilet Yes...those tales you've heard are true. The toilet was first patented in England in 1775, invented by one Thomas Crapper, but the extraordinary automatic device called the flush toilet has been around for a long time. Leonardo Da Vinci in the 1400's designed one that worked, at least on paper, and Queen Elizabeth I reputably had one in her palace in Richmond in 1556, complete with flushing and overflow pipes, a bowl valve and a drain trap. In all versions, ancient and modern, the working principle is the same. Tripping a single lever (the handle) sets in motion a series of actions. The trip handle lifts the seal, usually a rubber flapper, allowing water to flow into the bowl. When the tank is nearly empty, the flap falls back in place over the water outlet. A floating ball falls with the water level, opening the water supply inlet valve just as the outlet is being closed. Water flows through the bowl refill tube into the overflow pipe to replenish the trap sealing water. As the water level in the tank nears the top of the overflow pipe, the float closes the inlet valve, completing the cycle. From the oldest of gadgets in the bathroom, let's turn to one of the newest, the toothpaste pump. Sick and tired of toothpaste squeezed all over your sink and faucets? Does your spouse never ever roll down the tube and continually squeezes it in the middle? Then the toothpaste pump is for you! When you press the button it pushes an internal, grooved rod down the tube. Near the bottom of the rod is a piston, supported by little metal flanges called "dogs", which seat themselves in the grooves on the rod. As the rod moves down, the dogs slide out of the groove they're in and click into the one above it. When you release the button, the spring brings the rod back up carrying the piston with it, now seated one notch higher. This pushes one-notch's-worth of toothpaste out of the nozzle. A measured amount of toothpaste every time and no more goo on the sink. Refrigerators...
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