The Fairy-Land of Science

Even if I lay the paper on the table this is still true, because there is always some air under it. If, however, I could get the air quite away from one side of the paper, then the pressure on the other side would show itself. I can do this by simply wetting the paper and letting it fall on the table, and the water will prevent any air from getting under it. Now see! if I try to lift it by the thread in the middle, I have great difficulty, because the whole 15 pounds' weight of the atmosphere is pressing it down. A still better way of making the experiment is with a piece of leather, such as the boys often amuse themselves with in the streets. This piece of leather has been well soaked. I drop it on the floor and see! it requires all my strength to pull it up. (In fastening the string to the leather the hole must be very small and the know as flat as possible, and it is even well to put a small piece of kid under the knot. When I first made this experiment, not having taken these precautions, it did not succeed well, owing to air getting in through the hole.) I now drop it on this stone weight, and so heavily is it pressed down upon it by the atmosphere that I can lift the weight without its breaking away from it. Have you ever tried to pick limpets off a rock? If so, you know how tight they cling. the limpet clings to the rock just in the same way as this leather does to the stone; the little animal exhausts the air inside it's shell, and then it is pressed against the rock by the whole weight of the air above.