capable of being easily erected and examined, and not liable to get out of order.

The pressure-pipes, through which the motive force is transmitted, may be fixed against the sides of the shaft, where they occupy no useful space; they may be placed at any angle, and, provided sharp bends are avoided, the direction may be changed as often as required, without any appreciable loss from increased friction. When employed at surface, in place of flat-rods, they may be laid below ground, so as to be protected from the weather and out of the way of surface operations. The facilities which this system offers for the utilization of distant water-power, by laying the pipes in this way underground, constitute one of its most important features.

The loss of power in transmission being very little by this system, a great saving of coal is effected where steam-power is employed; and, as the pump is double, it utilizes the whole power of a water-wheel.

The valve consists of a vertical pipe, mounted upon a brass seating and a tubular, or ring weight, containing a portion of a brass ball-valve-which is dropped over the vertical pipe until the ball rests upon the seating, so sealing up the pipe until the pressure of steam becomes greater than the load of weights. As soon as this is the case the valve opens and the steam escapes. will be seen by the section that the number of weights can be lessened, or increased, as may be required, for various press ures. The valves can be made of any number of inches diameter.

It

The new Patent Groups of Valves (Fig. 2) are simply an

pressure in pounds per square inch on the boiler. The pith of difference between a large valve, say 5 inches diameter, which gives an extent of circular lip opening only 15 inches for the escape of steam, yet requires 1000 pounds weight to load the valve to 50 pounds pressure, in consequence of the area for same being 20 square inches.

The necessity for such a mass of metal for so small an opening and the cost for same, led the Inventor's intention to the adopting any number of small valves to get a greater extent of opening with a less dead weight, or five times the opening with the same weight that would be required to weight a 5-inch diameter valve.

It will be seen by the illustrated group of five valves that only one hole is required to penetrate the boiler, whatever be the number of valves in the group adopted. The various pipes are planted upon a tray, which is to be bolted to a block rivetted on the boiler to receive the same.

It will be seen, also, that, within the circle of valves, a bowl is placed, with snips in it corresponding with the number of valves; for the purpose of lifting the valves to ease the pressure of steam in the boiler, or for blowing away all the steam into the atmosphere when required.

ROOT'S PATENT ROTARY BLOWER.

Root's patent Rotary Blower, manufactured by Thwaites and Carbutt, of Bradford, Yorkshire, is fast superseding the Fan, for producing blasts at a moderate pressure, say up to 1 lbs. per

square inch. The maximum speed of the machine is 350 revolu

tions

per minute; and the power required to produce any given