Mosquito

Take a 20 mm by 150 mm test tube, insert a one-hole stopper with an 8-inch glass tube, attach two test tube clamps to either side for effect, and you have an artificial mosquito. To demonstrate the presence and effect of air pressure, all you have to do is light a candle, heat the bottom of the test tube for a minute, and then invert the glass tube in a cup full of water with red food coloring (blood, of course). As the air inside the test tube cools, the pressure will become lower than the pressure outside the tube, and water will get pushed up into the mosquito.

LL Demos & Labs: Wow, That’s a Little Sucker!