Steinmetz, Charles Proteus, 1865-1923, American electrical engineer, b. Breslau, Germany, studied at the Univ. of Breslau. Forced to flee Germany because of his socialist activities, he came to the United States in 1889. Rudolf Eickemeyer, who had just begun to build electrical apparatus in his factory in Yonkers, N.Y., gave him his start in electrical engineering research. When the General Electric Company bought out Eickemeyer in 1892, Steinmetz joined the new owners. He discovered the law of hysteresis, which made it possible to reduce the loss of efficiency in electrical apparatus resulting from alternating magnetism; developed a practical method of making calculations of alternating current, thus revolutionizing electrical engineering; and did valuable research on transient electrical phenomena (lightning). He built a generator that produced artificial lightning. Professor (1902-23) at Union College, Schenectady, N.Y., Steinmetz wrote many scientific papers and a number of standard texts. He remained a socialist and was president of the Schenectady board of education (1912-23) and of the common council (1916-23).

Proteus, in astronomy, one of the natural satellites, or moons, of Neptune.

Proteus, in Greek mythology, prophetic old man of the sea who tended the seals of Poseidon. He could change himself into any shape he pleased, but if he were nevertheless seized and held, he would foretell the future. The word protean is derived from his name.

orig. Karl August Rudolf Steinmetz

(born April 9, 1865, Breslau, Prussia—died Oct. 26, 1923, Schenectady, N.Y., U.S.) German-born U.S. electrical engineer. Forced to leave Germany because of his socialist activities, he emigrated to the U.S. in 1889 and began working for General Electric Co. in 1893. He taught at Union College from 1902. His experiments led to the law of hysteresis, which deals with power loss in electrical machinery when magnetic action is converted to unusable heat; the constant he calculated (by age 27) has remained a part of electrical engineering vocabulary. In 1893 he developed a simplified symbolic method of calculating alternating-current phenomena. He also studied electrical transients (changes of very short duration in electrical circuits; e.g., lightning); his theory of traveling waves led to development of devices to protect high-power transmission lines from lightning bolts and to the design of a powerful generator. He patented over 200 inventions.

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In Greek mythology, the prophetic old man of the sea and the shepherd of sea animals such as seals. He was subject to Poseidon. He knew all things—past, present, and future—but disliked telling what he knew. Those who wanted information from him had to catch him sleeping and bind him. He would try to escape by changing his form, but if a captor held him fast he gave the wished-for answer and plunged into the sea.

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orig. Karl August Rudolf Steinmetz

(born April 9, 1865, Breslau, Prussia—died Oct. 26, 1923, Schenectady, N.Y., U.S.) German-born U.S. electrical engineer. Forced to leave Germany because of his socialist activities, he emigrated to the U.S. in 1889 and began working for General Electric Co. in 1893. He taught at Union College from 1902. His experiments led to the law of hysteresis, which deals with power loss in electrical machinery when magnetic action is converted to unusable heat; the constant he calculated (by age 27) has remained a part of electrical engineering vocabulary. In 1893 he developed a simplified symbolic method of calculating alternating-current phenomena. He also studied electrical transients (changes of very short duration in electrical circuits; e.g., lightning); his theory of traveling waves led to development of devices to protect high-power transmission lines from lightning bolts and to the design of a powerful generator. He patented over 200 inventions.

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