Page:Popular Science Monthly Volume 15.djvu/315

Rh to rim heedlessly to waste down that great fall of 157 feet, in a sheet twenty feet thick and 4,750 feet broad?

The gas-wells of the oil regions have been permitted to spout away wealth enough to have repaid a hundred-fold all the money ever lost in oil speculations; but it is gratifying to be able to say that the great value of these natural supplies of heat and light is now very generally recognized, and that in many localities the gas is turned to useful account in supplying light and heat to towns and cities and factories and mills.

In some of the cases that I have called to your attention, the power is steady and unremitting, in others it is too violent or too uncertain for direct application. In the first instance, uses for the power may be found at once; in the last, means for storing it up must be provided, and would, beyond question, abundantly repay the undertaking. For this purpose, the raising of weights or of water into elevated reservoirs, and the compressing of air, afford two simple and ready means of storing up power to be let loose as required; while other means of a mechanical nature to accomplish the same purpose will readily occur to my mechanical hearers.

While upon this point, I must not omit to state one fact of the greatest interest that is now attracting the attention of some of the highest living authorities. I refer to the question of the practicability of transmitting mechanical power to great distances by converting it into electricity, through the agency of what are called dynamo-electric machines, and utilizing this either for the production of powerful lights for illuminating cities and towns, or by converting it back again into mechanical power with the aid of magneto-electric engines, by which mills, factories, and workshops may be furnished with the power they now obtain from steam or water. It will be very à propos, in this connection, to notice that the feasibility of transmitting to great distances the almost incredible power of Niagara Falls, by some such means as that above named, has been affirmed by many scientific investigators of eminence.

Dr. C. W. Siemens, in his presidential address before the last meeting of the Iron and Steel Institute, in touching upon the highly interesting subject of the employment of electricity as a substitute for steam, made the following instructive statements: He declared that so long as the source of electrical power depended upon the galvanic battery, it must, in the present state of things, remain far more expensive than steam-power, for the obvious reason that zinc, which is the fuel of the galvanic battery, is vastly more expensive than coal, the fuel of the steam-boiler. If, however, continues Dr. Siemens, a natural force, such as water-power, mark you, could be utilized to generate electricity economically, the case would be very different. A dynamo-electric machine actuated by water-power could be made to generate powerful electrical currents, which could be transmitted through