This weight has been before stated, viz., fourteen and a half pounds, such a weight being supported by every single square inch of the globe’s surface. A marvelous pressure is thus exerted on the whole earth. In other words, the weight of the air that surrounds the earth on all sides is no less than the following enormous number of 5,184,740,000,000,000 tons.

A man of average height, himself supports the enormous pressure of 34,171 pounds, or over 15 tons, and yet does not feel the least inconvenience in his movements. It is because this pressure is exercised in all directions, and a human body carries within it elastic fluids that counterbalance that tremendous weight.

So accustomed do people become to this weight that when the weather is stormy, a feeling of heaviness comes on.

However, it is just the contrary which takes place when the barometer is lower; that is to say, the atmospheric pressure has diminished. Consequently there is less weight to be carried.

You would experience the same sensation when going up in a balloon. As you rise higher and higher the weight of the air is less felt, and this makes people so uncomfortable that at a height of about 9,000 or 10,000 yards the liquids in our body—the blood, the water, the bile—tend to escape outwards. Why? Because they are no longer balanced by an outside pressure equal in force to them. In fact, if you continued to ascend, your fate would be that of the bladder in the first experiment—you would burst. Thus are you and all creatures attached to the face of the earth, and it seems as if great heights were forbidden to our curiosity.