The power is the force applied to the pump-handle. What is the fulcrum? The fulcrum is the screw that fastens the handle to the pump. What is the weight? The weight is the water raised by the bucket. Are scissors an example of the lever? Yes; scissors are a double lever. What is the fulcrum in the scissors? The fulcrum is the rivet which holds the two levers together. What is the power? The power is the force applied by the fingers. What is the weight? The weight is the paper, or other substance, to be cut by the scissors. Can scissors be made very strong? Yes; some scissors are made so strong that they are used for cutting iron, tin, and zinc. What other useful instruments are made upon the same principle as the scissors? Such instruments as nippers, pincers, tweezers, and blacksmith’s tongs. What is the second kind of lever? It is where the weight is between the power and the fulcrum, as is shown in Fig. 47. [Illustration: Fig. 47.] Of what use is this kind of lever? It is very useful in lifting heavy weights a short distance from the earth. What example is there of this kind of lever? The door on its hinges is a lever of this kind. What is the fulcrum? The hinges are the fulcrum. What is the weight? The door is the weight. What is the power? The force that opens or shuts the door is the power. What other examples of this kind of lever have we? We have an example in the lid of the tea-kettle, and in the cover of the ink-stand, when they are fastened on by hinges. What is the third kind of lever? It is where the power is between the fulcrum and the weight, as is shown in Fig. 48. [Illustration: Fig. 48.] What examples of this kind of lever have we in common use? The shovel, the spade, and the pitch-fork, are levers of this kind. What is the fulcrum? One hand is the fulcrum. What is the power? The other hand is the power. What is the weight? The earth raised on the shovel is the weight. What other familiar example have we of this kind of lever? The fishing-rod is an example of this kind. One hand is the fulcrum, the other hand is the power, and the line, with the fish, is the weight. This is made plain by Fig. 49, representing a lad just drawing a fish out of the water. [Illustration: Fig. 49.] There are several other examples of this kind of lever; will you name some of them? Yes; brooms, hoes, rakes, and axes are all levers of this kind. What is the first kind of lever mentioned? It is where the fulcrum is between the power and the weight, as in Fig. 50. [Illustration: Fig. 50.] What is the second kind of lever mentioned? It is where the weight is between the power and the fulcrum, as in Fig. 51. [Illustration: Fig. 51.] What is the third kind of lever mentioned? It is where the power is between the fulcrum and the weight, as in Fig. 52. [Illustration: Fig. 52.] Wheel and Axle.