Black Diamond Coal Mining Company v. Excelsior Coal Company

This was an action at law by the Excelsior Coal Company to recover damages for the infringement of reissued letters patent No. 7,341, granted October 10, 1876, to Martin R. Roberts, for an 'improvement in coal screens and chutes.'

It seems by the statement of the patentee that, previous to this invention, in unloading vessels of coal the coal had, for the most part, been hoisted from the hold, over the bulwarks, and dumped upon the wharf or upon the coal previously dumped, or, if chutes were used, such chutes were fixed; nor, so far as the patentee was aware, had a movable chute ever been known or used by which the coal could be received from the vessel at any point on the wharf, and be screened and delivered to the cart. The patentee further states in his specification: 'My invention consists of a portable apparatus for receiving coal from the bucket by which it is hoisted from the ship, and for screening and delivering it to carts on the wharf, said apparatus being adapted for ready removal from place to place when required.'

'By this apparatus I am able to save repeated handlings and cosequent expense and the breakage of the coal, and the apparatus can be changed from one point to another where the vessel may be placed.'

The invention is shown in the following drawing:

The invention in question consisted substantially of a strong frame, A, surmounted by a hopper, B, B', in the form of a trough, into which the coal is dumped from the hoisting buckets. The coal falls through the hopper upon an inclined screen, D, whose meshes, constructed of horizontal wires, are coarse enough to detain only the larger lumps, which accumulate in a reservoir, O, formed by the screen on one side, and three inclined surfaces on the other. This reservoir is in fact a secondary hopper at the bottom of which is located a chute, F, and gate, h, through which the large coal is drawn off, as required, into the cart or other vehicle. The smaller coal, which passes through the meshes of the screen, D, falls upon a second inclined screen, I, standing transversely to the upper one, whose meshes are finer than the other. The coal is again shifted by this screen into two grades, the coarser of which is discharged down the incline at one side of the machine, while the finer falls through the meshes upon the floor or wharf beneath the frame.

The patentee further added in his specification: 'The frame, A, A, will be mounted upon small wheels, so that it can be moved from one place to another upon a wharf, in order to be placed in position to receive the discharging cargo of different ships; but when moving it from one wharf to another I employ axles across each end of the frame, upon which strong wheels are placed, so that the entire machine can be drawn along similar to any vehicle. * * * When it is not desired to screen the article or substance to be unloaded, a false bottom or metal blank, K, is placed upon the grating or inclined side, D, of the reservoir, so that the substance will be carried directly through the chute into the cart or wagon intended to convey it away.'

Plaintiff relied upon an infringement of all the claims of the patent, which read as follows:

'(1) A portable combined coal receiving, screening, and delivering apparatus, arranged to receive the coal or other cargo from a swinging suspended tub or bucket, by which it is hoisted from the hold of a ship or other watercraft, and to screen it automatically, and deliver it into carts; said apparatus being constructed and arranged substantially as described.

'(2) The receiving hopper, B, B', in combination with the reservoir, O, with its screen or grating side, D, chute, F, with its toothed gate, h, and one or more independent screens, I, all combined and arranged substantially as and for the purpose above described.

'(3) The metal blank or false bottom, K, in combination with the receiving hopper, B, B', reservoir, O, chute, F, and gate, h, substantially as and for the purpose above described.

'(4) The combination of the hopper, B, B', for receiving the coal from a swinging bucket, the reservoir, O, arranged to receive the coal as it passes from the hopper, with the chute, F, and gate, h, all constructed to operate substantially as and for the purpose set forth.

'(5) In combination with the elongated hopper, the screen, D, reservoir O, and chute, F, with its gate, h, the cumbination being substantially as is herein set forth.'

The case was tried before a jury, and resulted in a verdict of $8,830.90 for the plaintiff, upon which a judgment was subsequently entered. To review this judgment the Black Diamond Coal Mining Company, defendant therein, sued out this writ of error.

M. M. Estee, W. W. Dudley, and L. T. Michene, for plaintiff in error.

Chas. R. Miller and John L. Boone, for defendant in error.

Mr. Justice BROWN, after stating the facts in the foregoing language, delivered the opinion of the court.