e50 ^BDEBIL BEPOBTEBï �in patent No. 132,111, nor could the devices in patent No. 132,111, for combining the two oylinders, be substituted 8o as to combine the two cylinders, or pistons, as shown and described in patent No. 172,896; andthat for these reasons he regards the inventions set forth in the two patents as entirely different in their construction and mode of operation in every respect, except the ' mere faot of their having two cylinders, and their pistons, to assist each other in lifting the load. The plaintiff 's expert, Mr. Mcintyre, says that the arrangement described in patent No. 172,896 is substan- tially like that shown in patent No. 132,111, in the main and particular features of construction and mode of operation, namely: the eombination with the shaft çr cross-head (or other device, as the case may be, for opera ting the cable) of the pistons of several cylinders, in such a manner that each of said pistons is always in direct and operative connection with the cros3»head or device to be driven by the piston, and so that either one of the cylinders and pistons may be brought into use as a re-enforce to the other, after such other shall have partially raised the load to be elevated ; that the machine shown in patent No. 172,896, while it involves the main feature and important principle of construction and mode of operation which is the subject of the machine in patent No. 132,111, is supplemented with the idea of such a eombination and arrangement of the cylinders as that one shall be ooncentrically within another, and as that, whether one or the other be employed, or both at the same time, the power exerted through the connection of the piston with the shaft or other device to be driven will be transmitted centrally to the shaft to be moved, and in a more desirable manner than is accomplished by the construction shown in patent No. 132,- 111 ; and that the machine in patent No. 172,896 embraces an improvement on the machine shown in patent No. 132,111, in that the several pistons and piston-rods, which are always in operative connectin with the shaft or thing to be driven by them, are always so supplied with water, in contact with the pistons, that when the water pressure is applied to either pis- ����