Science for beginners . ers where it would be most useful. 592. Transmission of Power.—Recently it has been foundpossible to transmit energy in the form of electric current adistance of 200 miles with profit. On the map (Fig. 301),a circle with a 200 mile radius has been drawn about thepower plants at Niagara Falls and at Keokuk, Iowa. Anypoint lying within these circles may easily be supplied withpower from these plants. St. Louis, Missouri, 137 miles dis-tant, is now consuming the larger portion of the power gen-erated at Keokuk (Fig. 302). Much of the power gener-ated at Niagara Falls is so
Science for beginners . ers where it would be most useful. 592. Transmission of Power.—Recently it has been foundpossible to transmit energy in the form of electric current adistance of 200 miles with profit. On the map (Fig. 301),a circle with a 200 mile radius has been drawn about thepower plants at Niagara Falls and at Keokuk, Iowa. Anypoint lying within these circles may easily be supplied withpower from these plants. St. Louis, Missouri, 137 miles dis-tant, is now consuming the larger portion of the power gen-erated at Keokuk (Fig. 302). Much of the power gener-ated at Niagara Falls is sold in the cities of western NewYork. Many of the cities on the coast of California receivepractically all their power from hydro-electric plants lo-cated many miles distant in the Sierra Nevada Mountains. SOME COMMON MECHANICAL MOTORS 499 The Steam Engine593. Importance of the Steam Engine.—No other deviceor machine invented by man has had as great an influenceupon the material advancement of civilization as has the. Fig. 302.—Line for transmission of electric power from Keokuk to St. Louis. steam engine. It is estimated that the steam engines of theworld are today doing from 150 to 200 million horse-power ofwork. This is many times the amount of work the entirepopulation of the civilized world could do were every adulthuman being working daily at hard manual labor. The steam 500 MACHINES, WORK* AND ENERGY engine during the last century has largely freed civilized manfrom hard labor. It has made possible the mine, the mill, thefactory, the steam ship, and the railroad. It has made manalmost the complete master of the physical forces of theworld. 594. Use of the Earliest Steam Engines.—It was just atthe beginning of the 18th century (1700) that the steamengine first began to be recognized as a useful the 18th century, however, practically the only useto which it was put was the pumping of water from the minesof England. Before the invention of the steam en
Size: 1542px × 1620px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, booksubjectscience, bookyear1921
