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 a big tank or boiler is not needed to store the gas. It is made as it is needed, and used up as fast as it is made. When an automobile passes you, you can hear these little explosions that make it go.

WHY WASHINGTON’S EYES FOLLOW US
There is one picture of Washington in which the eyes follow any one who looks at it. It is the portrait painted by an American artist, Gilbert Stuart. The eyes are very large and mild and noble. They seem to look at every boy and tell him to be brave and unselfish and to love his country. That is one reason why we think this the best of all portraits of the father of our country. The face, and especially the eyes, speak so plainly the character of the man. The secret of the eyes is that Washington and the artist were looking straight at each other when the eyes were painted. Eyes that follow the gazer are to be found in "Mona Lisa" and many of the world's greatest paintings. They are to be found in good photographs, too. If the sitter looks straight into the camera, his eyes in the photograph will gaze back, at any angle, into the eyes of any one who looks at it.

WHAT RINGS THE DOOR BELL?
A current of electricity running around a wire, rings the door bell. Then why doesn’t it ring all the time? For the same reason that an electric lamp doesn’t give light all the time. In both cases we connect and break the current of electricity. The carbon filament in the lamp runs into platinum wires in the neck. When you push in a button or turn a thumb key, the platinum wires are made to touch the copper wire that carries the electric current into the house. The current flows around the carbon filament completing the circuit, and we get a light. So, when you press the button of a door bell a bit of metal under the button presses on the wire that, all the time, carries the electric current to that point. The current instantly leaps along the rest of the wire to the bell, and rings it. In the case of the lamp the current comes from a distant power house on wires, under the streets, between the walls and through the tubing of the electric light fixtures. In the case of the door bell, each house has its own little power plant in the basement, or on a closet shelf. It is an electric battery made with chemicals in a jar. Any careful, clever boy can make such a battery, and explain to a school just how a door bell is made to ring.