[Footnote: A paper read before the Engineers' Club of St. Louis, 1884.]

By JAMES W. HILL.

In the history of the world the utilization of the wind as a motive power antedates the use of both water and steam for the same purpose.

The advent of steam caused a cessation in the progress of wind power, and it was comparatively neglected for many years. But more recently attention has been again drawn to it, with the result of developing improvements, so that it is now utilized in many ways.

The need in the West of a motive power where water power is rare and fuel expensive has done much to develop and perfect wind mills.

Wind mills, as at present constructed in this country, are of recent date.

The mill known as the "Eclipse" was the first mill of its class built. It is known as the "solid-wheel, self-regulating pattern," and was invented about seventeen years ago. The wind wheel is of the rosette type, built without any joints, which gives it the name "solid wheel," in contradistinction to wheels made with loose sections or fans hinged to the arms or spokes, and known as "section wheel mills."

The regulation of the Eclipse mill is accomplished by the use of a small adjustable side vane, flexible or hinged rudder vane, and weighted lever, as shown in Plate 1 (on the larger sizes of mills iron balls attached to a chain are used in place of the weighted lever). The side vane and weight on lever being adjustable, can be set to run the mill at any desired speed.

Now you will observe from the model that the action of the governing mechanism is automatic. As the velocity of the wind increases, the pressure on the side vane tends to carry the wind wheel around edgewise to the wind and parallel to the rudder vane, thereby changing the angle and reducing the area exposed to the wind; at the same time the lever, with adjustable weight attached, swings from a vertical toward a horizontal position, the resistance increasing as it moves toward the latter position. This acts as a counterbalance of varying resistance against the pressure of the wind on the side vane, and holds the mill at an angle to the plane of the wind, insuring thereby the number of revolutions per minute required, according to the position to which the governing mechanism has been set or adjusted.

If the velocity of the wind is such that the pressure on the side vane overcomes the resistance of the counter weight, then the side vane is carried around parallel with the rudder vane, presenting only the edge of the wind wheel or ends of the fans to the wind, when the mill stops running.

This type of mill presents more effective wind receiving or working surface when in the wind, and less surface exposed to storms when out of the wind, than any other type of mill. It is at all times under the control of an operator on the ground.

A 22-foot Eclipse mill presents 352 square feet of wind receiving and working surface in the wind, and only 9½ square feet of wind resisting surface when out of the wind.

Solid-wheel mills are superseding all others in this country, and are being exported largely to all parts of the world, in sizes from 10 to 30 feet in diameter. Many of these mills have withstood storms without injury, where substantial buildings in the immediate vicinity have been badly damaged. I will refer to some results accomplished with pumping mills:

In the spring of 1881 there was erected for Arkansas City, Kansas, a 14-foot diameter pumping wind mill; a 32,000-gallon water tank, resting on a stone substructure 15 feet high, the ground on which it stands being 4 feet higher than the main street of the town. One thousand four hundred feet of 4-inch wood pipe was used for mains, with 1,200 feet of 1½-inch wrought iron pipe. Three 3-inch fire hydrants were placed on the main street. The wind mill was located 1,100 feet from the tank, and forced the water this distance, elevating it 50 feet. We estimate that this mill is pumping from 18,000 to 20,000 gallons of water every twenty-four hours. We learned that these works have saved two buildings from burning, and that the water is being used for sprinkling the streets, and being furnished to consumers at the following rates per annum: Private houses, $5; stores, $5; hotels, $10; livery stables, $15. At these very low rates, the city has an income of $300 per annum. The approximate cost of the works was $2,000. This gives 15 per cent. interest on the investment, not deducting anything for repairs or maintenance, which has not cost $5 per annum so far.

Plate 2. THE ECLIPSE WIND MILL.

In June, 1883, a wind water works system was erected for the city of McPherson, Kansas, consisting of a 22-foot diameter wind mill on a 75-foot tower, which pumps the water out of a well 80 feet deep, and delivers it into a 60,000-gallon tank resting on a substructure 43 feet above the ground. Sixteen hundred feet of 6-inch and 300 feet of 4-inch cast iron pipe furnish the means of distribution; eight 2½-inch double discharge fire hydrants were located on the principal streets. A gate valve was placed in the 6-inch main close to the elbow on lower end of the down pipe from the tank. This pipe is attached to the bottom of the tank; another pipe was run up through the bottom of tank 9 feet (the tank being 18 feet deep), and carried down to a connection with the main pipe just outside the gate valve. The operation of this arrangement is as follows:

The gate valve being closed, the water cannot be drawn below the 9-foot level in tank, which leaves about 35,000 gallons in store for fire protection, and is at once available by opening the gate valve referred to. The tank rests on ground about 5 feet above the main streets, which gives a head of 57 feet when the tank is half full. The distance from tank to the farthest hydrant being so short, they get the pressure due to this head at the hydrant, when playing 2-inch, or 1-1/8-inch streams, with short lines of 2½-inch hose; this gives fair fire streams for a town with few if any buildings over two stories high. It is estimated that this mill is pumping from 30,000 to 38,000 gallons on an average every twenty-four hours. There is an automatic device attached to this mill, which stops it when the tank is full, but as soon as the water in the tank is lowered, it goes to pumping again. The cost of these works complete to the city was a trifle over $6,000.