853. Why does the alteration of the arrangement of the mouth, affect the formation of the sounds?
Because it sends the air to the tongue of the harp in a greater or lesser degree of compression.
"Hear, ye children, the instruction of a father, and attend to know understanding."—Proverbs iv.
854. Why does the pressure applied to the handle of an air pistol propel the cork?
Because, between the cork A and the air-tight piston C, there is a closed chamber of air b. When the handle D, which moves the piston C, is rapidly pushed in, it compresses the air until it is so much condensed, that it forces out the cork A.
