Page:The chemical history of a candle.djvu/142

140 about it. When the air is pumped from underneath the bladder which is stretched over this glass, you will see the effect in another shape: the top is quite flat at present, but I will make a very little motion with the pump, and now look at it see how it has gone down, see how it is bent in. You will see the bladder go in more and more, until at last I expect it will be driven in and broken by the force of the atmosphere pressing upon it. [The bladder at last broke with a loud report.] Now, that was done entirely by the weight of the air pressing on it, and you can easily understand how that is. The particles that are piled up in the