DBDERICK V. CASSELL. 315 �for placing it in the press-box under the traverser. It is for an improvement added to the press in 1874. A similar screen is tound in the Wallen patent for "baling- presses," of 1872, — inserted in the bottom of the press-box, and partly, at least, under the traverser, or the space over which it passes, designed for the same use, and answer- ing for the same purpose as in the plaintiff's. That it is less service- able in the Wallen press is not important. This resulta not from any difference in the device, or its location in the box, or combination -with the traverser or other parts of the press, but from the difference in the presses themselves, and in the methods of forming baies. In Wallen's the baie is formed in the press-box, into which the required quantity of hay is placed before any pressure is applied, thus afford- ing but little opportunity for the escape of dust through the screen below ; while in the plaintiff's the baie is formed in a separate cham- ber, into which each forkful of hay is pushed, as pitohed in, thus allowing the dust of each in succession, to fall upon and pass through the screen. This difference, or peculiarity of construction in the plain- tiff's press, does not aid his claim for the improvement under consid- eration. The press, as we have seen, is covered by previously-issued patents. He is entitled to no greater consideration as respects this improvement of it, than a stranger would have been, if he had made it. His claim can only be, as in terms it is, for adding a screen to the press previously constructed and patented, just as he did it. In this view it is plain that what he did was but copying what Wal- len had donc. There was nothing whatever new about it. The claim is therefore disallowed. �Of reissue 8,296, the only claim involved is the following: "(1) The press-case provided with one or more apertures, '0, for the pur- pose set for th." �We do not find any valid objection to this claim, which is, as the one preceding was, for an improvement. It was a useful addition, and was novel. That it was not inserted in the original patent for the improvement is unimportant. It is very plainly described in the specifications; and, although an occasional use of it only, was then oontemplated, the propriety of inserting it in the reissue cannot now be questioned. �This disposes of the several claims, so far as respects the question of validity. The question of infringement need not oceupy much more time than bas already been devoted to it, in contrasting the two presses as complete or entire machines. To the third, fifth, tenth and eleventh claims of 8,130, and the third of 8,316, which ��� �