BTEBBINS, ETC., BLEVATOE MANOf'g CO. V. STEBBINS. 449 �main -working piston the pressure of water -willalso flow into the assisting cylinder, so as to fill up the space undemeath the assisting working piston, which is directly connected with the cross-head ; that said assisting piston and its cylinder are pro- vided with a second piston, and so arranged relatively to the water pressure that whenever the attendant of the machine desires an extra amount of force to lift the load, he opens a valve to admit the water pressure underneath said second piston, and its force is thereby immediately applied upon or against the assisting piston ; and that these two cylinders and their pistons are combined by means of a cross-head. The eame expert says that the invention set forth in patent No. 132,111 and that set forth in patent No. 172,896 resemble each other only in the fact of having two cylinders so arranged in a hydraulic elevator as to be capable of assisting each other in lifting the load, according to the pleasure of the operator or attendant of the machine; that in so far as relates to the arrangement of the cylinders and the means of combining them together, they are, in his opinion, entirely different in their construction and mode of operation ; that the arrange- ment of the cylinders as shown in patent No. 132,111 consista simply in placing one beside the other in a line, so that their pistons may be connected with a line of shafting, the only means of their combination being the shaft which carries the pinions which gear into the racks of the several cylinders- in the combination; that in patent No. 172,896 the arrangement is such that only two pistons, with their cor^ responding cylinders, can be connected so as to assist each other, one of them being placed inside of the other, thereby arranging them so that the two may be connected directly with the cross-head which carries the sheaves over which the lifting ropes work, there being no racks or pinions or gear- ing of any kind between the two pistons which are intended to assist each other, but both of said pistons being connected directly with the same piece of mechanism ; that the com- bination and arrangement in patent No. 172,896 eould not be Bubstituted to operate in combination with the device described T.4,no.5— 29 ����
