So nearwith only the plate-glass between him and the bright discs!

Q.What is the advantage of two discs entering into the composition of the crank instead of one? A.A double crank, such as two discs form with the crank pin, is a much steadier combination than would result if only one disc were employed with an over-hung pin.

Q.What is the advantage of two discs entering into the composition of the crank instead of one? A.A double crank, such as two discs form with the crank pin, is a much steadier combination than would result if only one disc were employed with an over-hung pin.

The inlet and outlet valves of the air pump consist of brass plates 1/2 inch with strong feathers across them, and in each plate there are six grated perforations covered by india rubber discs 7 inches in diameter.

Q.What are the constructive peculiarities of the discs and crank pin?

A.The discs, which are 64 inches diameter, are formed of cast iron, and are 2-1/2 inches thick in the body, and 5 inches broad at the rim.

It is secured at the ends to the discs by flanges 18 inches diameter, and 2 inches thick.

These flanges are indented into thickened parts of the discs, and are each attached to its corresponding disc by six bolts 2 inches diameter, countersunk in the back of the disc, and tapped into the malleable iron flange.

Each crank shaft bearing is similarly perforated, and pipes are cast in the discs connecting these perforations together.

The result of this arrangement is, that a large part of the oil or water fed into the bearings of the shaft is driven by the centrifugal action of the discs to the surface of the crank pin, and in this way the crank pin may be oiled or cooled with water in a very effectual manner.

To intercept the water or oil which the discs thus drive out by their centrifugal action, a light paddle box or splash board of thin sheet brass is made to cover the upper part of each of the discs, and an oil cup with depending wick is supported by the tops of these paddle boxes, which wick is touched at each revolution of the crank by a bridge standing in the middle of an oil cup attached to the crank pin.

To intercept the water or oil which the discs thus drive out by their centrifugal action, a light paddle box or splash board of thin sheet brass is made to cover the upper part of each of the discs, and an oil cup with depending wick is supported by the tops of these paddle boxes, which wick is touched at each revolution of the crank by a bridge standing in the middle of an oil cup attached to the crank pin.

Between the side of the disc and the side of the contiguous bearings there is a short neck extending 4-3/4 inches in the length of the shaft, and hollowed out somewhat to permit the passage of the piston rod; for one piston rod passes immediately above the shaft on the one side of the discs, and the other piston rod passes immediately below the shaft on the other side of the discs.

Between the side of the disc and the side of the contiguous bearings there is a short neck extending 4-3/4 inches in the length of the shaft, and hollowed out somewhat to permit the passage of the piston rod; for one piston rod passes immediately above the shaft on the one side of the discs, and the other piston rod passes immediately below the shaft on the other side of the discs.

The speed of piston with this number of strokes is 700 feet per minute, and the engine works steadily at this speed, the shock and tremor arising from the arrested momentum of the moving parts being taken away by the counterbalance applied at the discs.

Direct acting screw engine by Messrs. John Bourne &, Co., cylinder; discs; guides; screw shaft brasses; air pump; slide valve; balance piston; connecting rod; piston rods; cross head; air pump arm; feed pump; crank pin; screw shaft; thrust plummer block; link motion; screw propeller.

Discs of direct acting screw engine instead of crank.

We have found also many curious objects of slate formation, resembling hollowed-out cups, discs, and two well formed resemblances of a leg and foot, and many other curious objects which Nature in her most capricious mood has scattered over this watery solitude.

Their shop on the Greene plantation had been forced by a mob even before their patent was procured in 1793, and Jesse Bull, Charles M. Lin and Edward Lyons, collaborating near Wrightsboro, soon put forth an improved gin in which saw-toothed iron discs replaced the wire points of the Whitney model.

It's no just the siller there's to be earned frae the wee discs, though there's a muckle o' that.

"Buy sheet lead," I said, "stamp it into discs.

Here the hedge is all hung with briony or traveller's joy; there is a burst of wild-roses, pale discs of faintest rose-jacinth, each with a full-seeded heart.

As to the burning discs at the spring festivals, see above, pp. 116 sq., 119, 143.

Less widespread are the customs of hurling lighted discs into the air and trundling a burning wheel down hill; for to judge by the evidence which I have collected these modes of distributing the beneficial influence of the fire have been confined in the main to Central Europe.

Safe in the branching vine, Pillowed on woven grasses sweet, Our pearly treasures shine; And all day long in the sunlight, By vernal breezes fanned, The daffodil and the jonquil Their jeweled discs expand; And two and fro, as the west winds blow, In the airy house a-swing, The feeble life in the pearly eggs She warms with brooding wing!