elO rSCEBAL BEPOBTEIi. �tially the inner chamber of the soeket. These arms bear upon the inner walls of the soeket; the shoulders at the other end of the hub bear also upon the side walls, so that the boit is supported at each end, and is moved endwise with the case on these supporta. The bottom of the shell forma an abut- ment to the spring, as in the plaintiff's catcli. �The enlarged shoulders and radical arms prevent the boit from being inserted in the case through its outer end. The case is left open at the inner end and the boit is there inserted, the arm, upon which is the thumb pad, being bent over 80 as to bring its outer end substantially in front of the opposite end of the boit. After the thumb pad bas passed through the orifice in the outer end of the case, the boit is turned one-quarter revolution, and is also passed through the orifice until it is stopped by the shoulders. The spring is then placed in the soeket of the hub and the bottom of the case ia placed in position. �This form of boit was new at the date of the Babcock patent. It is not the Converse boit, known as Exhibit 9, which, although it has the spring receiving soeket in the hub, is differently constructed with respect to the sides of the hub, and to the position of the sliding shoulder. Had the defend- ants' boit been known at the date of the patent, the general funetions of the two bolts being the same, the substitution would have been simply a substitution of one well-known boit for another, whieh performed the same office, and the change would have been formai. But the stem of the boit is new, and while the general window locking function of the two bolts is the same, the change in the method of construc- tion is not merely formai, but îs a change in the principle upon which the stem is made. The plaintiff's stem had its bearing in the hole in the bottom of the case. This com- pelled the stem to protrude through the bottom of the case when the boit was pressed inwards. The defendants' stem has its bearings entirely upon the walls of the case, which therefore is wholly closed except in front. Whether this is an advantage or not, I do not know. In consequence of the bolts coming in direct contact with the bottom cf t'.e casa ��� �
