He long afterward began to study chimneys, and after much experiment found that those that smoked need not be taken down, but that only a draught was needed to cause the smoke to rise in rarefied air. The name of the Franklin stove added very greatly to Poor Richard's wisdom, in making for Franklin an American reputation, which also extended to Europe. His fame arose along original ways. Surely no one ever walked in such ways before. He formed a club called the Junto, which became very prosperous, and gave strength to his local reputation. He also began a society for the study of universal knowledge, which was called the Philosophical Society. A man can do the most when he is doing the most. One thing leads to another; one thing feeds another, and one does not suffer in health or nerves from the many things that one loves to do. It is disinclination or friction that wears one down. People who have been very busy in what they most loved to do have usually lived to be old, and come down to old age in the full exercise of their powers. While Franklin was thus seeking how he could make himself useful to every one in many ways--for a purpose of usefulness finds many paths--his attention was called to a very curious discovery that had been made in the Dutch city of Leyden, in November, 1745. It was an electrical bottle called the Leyden jar. Nature herself had been discharging on a stupendous scale her own Leyden jars through all generations, but no one seems to have understood these phenomena until this memorable year brought forth the magical little bottle which was a flashlight in the long darkness of time. The Greeks had found that amber when rubbed would attract certain light substances, and the ancient philosophers and doctors had discovered the value of an electric shock from a torpedo in rheumatic complaints; that sparks would follow the rubbing of the fur of animals in cold air had also been noticed, but of magnetism, and of electricity, which is a current of magnetism, the world was ignorant, except as to some of its more common and obvious effects. In 1600 Dr. Gilbert, of England, discovered that many other substances besides amber could be made to develop an attractive power. He also discovered that there are many substances that can not be electrically excited. In 1650 Otto von Guericke, the inventor of the air-pump, made a machine which looked like a little grindstone--a wheel of sulphur mounted on a turning axle, which being used with friction produced powerful electrical sparks and lights. He found by experiments with this machine that bodies thus exerted by friction may impart electricity to other bodies, and that bodies so electrified may repel as well as attract. Sir Isaac Newton made an electrical machine of glass, and Stephen Gray, in 1720, said that if a large amount of electricity could be _stored_, great results might be expected from it.