Scientific American Supplement, No. 288, July 9, 1881

by Various

The water powers I have named are but a small fraction of the whole amount existing in the United States and the adjoining Dominion of Canada. There is Niagara, with its two or three millions of horse power; the St. Lawrence, with its succession of falls from Lake Ontario to Montreal; the Falls of St. Antony, at Minneapolis; and many other falls, with large volumes of water, on the upper Mississippi and its branches. It would be a long story to name even the large water powers, and the smaller ones are almost innumerable. In the State of Maine a survey of the water power has recently been made, the result, as stated in the official report, being "between one and two millions of horse power," part of which will probably not be available. There is an elevated region in the northern part of the South Atlantic States, exceeding in area one hundred thousand square miles, in which there is a vast amount of water power, and being near the cotton fields, with a fine climate, free from malaria, its only needs are railways, capital, and population, to become a great manufacturing section.

The design and construction of the works for developing a large water power, together with the necessary arrangements for utilizing it and providing for its subdivision among the parties entitled to it according to their respective rights, affords an extensive field for civil engineers; and in view of the vast amount of it yet undeveloped, but which, with the increase of population and the constantly increasing demand for mechanical power as a substitute for hand labor, must come into use, the field must continue to enlarge for a long time to come.

There are many cases in which the power of a waterfall can be made available by means of compressed air more conveniently than by the ordinary motors. The fall may be too small to be utilized by the ordinary motors; the site where the power is wanted may be too distant from the waterfall; or it may be desired to distribute the power in small amounts at distant points.[1] A method of compressing air by means of a fall of water has been devised by Mr. Joseph P. Frizell, C.E., of St. Paul, Minnesota, which, from the extreme simplicity of the apparatus, promises to find useful applications. The principle on which it operates is, by carrying the air in small bubbles in a current of water down a vertical shaft, to the depth giving the desired compression, then through a horizontal passage in which the bubbles rise into a reservoir near the top of this passage, the water passing on and rising in another vertical or inclined passage, at the top of which it is discharged, of course, at a lower level than it entered the first shaft.

[Footnote 1: Journal of the Franklin Institute for September, 1877.]

The formation at waterfalls is usually rock, which would enable the passages and the reservoir for collecting the compressed air to be formed by simple excavations, with no other apparatus than that required to charge the descending column of water with the bubbles of air, which can be done by throwing the water into violent commotion at its entrance, and a pipe and valve for the delivery of the air from the reservoir.

The transfer of power by electricity is one of the problems now engaging the attention of electricians, and it is now done in Europe in a small way. Sir William Thomson stated in evidence before an English parliamentary committee, two years ago, that he looked "forward to the Falls of Niagara being extensively used for the production of light and mechanical power over a large area of North America," and that a copper wire half an inch in diameter would transmit twenty-one thousand horse power from Niagara to Montreal, Boston, New York, or Philadelphia. His statements appear to have been based on theoretical considerations; but there is no longer any doubt as to the possibility of transferring power in this manner--its practicability for industrial purposes must be determined by trial. Dr. Paget Higgs, a distinguished English electrician, is now experimenting on it in the City of New York.

Great improvements in reaction water wheels have been made in the United States within the last forty years. In the year 1844, the late Uriah Atherton Boyden, a civil engineer of Massachusetts, commenced the design and construction of Fourneyron turbines, in which he introduced various improvements and a general perfection of form and workmanship, which enabled a larger percentage of the theoretical power of the water to be utilized than had been previously attained. The great results obtained by Boyden with water wheels made in his perfect manner, and, in some instances, almost regardless of cost, undoubtedly stimulated others to attempt to approximate to these results at less cost; and there are now many forms of wheel of low cost giving fully double the power, with the same consumption of water, that was obtained from most of the older forms of wheels of the same class.

ANCHOR ICE.

A frequent inconvenience in the use of water power in cold climates is that peculiar form of ice called anchor or ground ice. It adheres to stones, gravel, wood, and other substances forming the beds of streams, the channels of conduits, and orifices through which water is drawn, sometimes raising the level of water courses many feet by its accumulation on the bed, and entirely closing small orifices through which water is drawn for industrial purposes. I have been for many years in a position to observe its effects and the conditions under which it is formed.

The essential conditions are, that the temperature of the water is at its freezing point, and that of the air below that point; the surface of the water must be exposed to the air, and there must be a current in the water.