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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1883 edition. Excerpt: ...mechanism which would stop one of the machines, and so increase the speed of the others, until the head got to 18 feet, when another would be brought to rest in the same manner. Thus, when the head of water decreased to 1 foot, all the motors would be working one electric machine, instead of one each. When the motors ceased working, all the machines would be automatically put into gear with the shaft again, which would then be held in one position until released at the next working time by the action of a tidal clock, or a float would suffice, except that as it would always start the motors when the outside water had reached a certain level, most of the extra energy obtainable from the spring tides would be lost. A float at the inclosure side of the dam could be used instead of governor-balls to disconnect the generators, as the head of water decreased, or clockwork could be employed for the purpose. Instead of adapting the work to the decreasing energy, the latter could be maintained nearly constant, if a great number of motors were employed in proportion to the power derivable from the inclosure, and many of the electric machines could be dispensed with, as some of the motors instead of them could then remain at rest during part of the working time. In an extreme case, only one of the twenty generators in the former example would be necessary, if only one motor in the set of twenty was allowed to work when the head of water was greatest, and as it decreased others could be started, until at last all the motors would work the one machine. These two ways of maintaining the proper relationship between the energy and the work, could be combined by having ten electric machines driven at first by ten motors, which could be gradually increased to...
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Product details

  • Paperback | 74 pages
  • 189 x 246 x 4mm | 150g
  • Miami Fl, United States
  • English
  • black & white illustrations
  • 1236637593
  • 9781236637598