Our wife is an artist – a very good one we might add without bias. Among the devices that she has in her studio is a tube wringer. See picture below.
To understand why an artist would want such a device, consider that a 15ml tube of watercolour paint can cost $10 or more. So as an artist, you want to get every fractional milliliter of paint that you can out of the tube. For the non-artist, they are great for taming that almost empty tube of toothpaste.
To use the device, merely open the end opposite the hinges to allow the end of the tube to be inserted between the fluted rollers, close the device holding it with your left hand and turn the knob with your right hand. The rollers draw the tube in forcing the contents to the top.
So far so good. But when we tried a new tube wringer that our wife had just inherited, the tube kept falling out when we turned the knob. Perhaps we didn’t have it in far enough to start. Nope. Finally we realized that when turning the knob with our right hand – in a natural clock-wise direction – the wringer was actually expelling the tube. To use it we either had to turn the knob counter-clockwise, an unnatural operation for us, or switch hands, again an unnatural operation. The question remains: has our wife inherited a left-handed tube wringer?
And then, early this morning, lying in bed, we tried an experiment. With our right hand. We made a clockwise twisting motion and a counter-clockwise twisting motion. The mechanics of the hand and wrist give one a larger range of motion in the clockwise direction. Try it (use your right hand unless you prefer to use your other hand).
The rather neat insight is that being a largely right-handed species, we have a natural and logical bias to clockwise motion. This extends particularly to screwing. We make nuts and bolts and screws with right-handed threads, except in exceptional circumstances. And our clocks don’t run backward (right bias, right? Not left, right?).
Whose on first and why do runners in baseball run counterclockwise?
This is one of the great comedy sketches of the Monty Python caliber, if you haven’t seen it.