“Error to the Circuit Court of Pennsylvania. This was an action for the infringement of the same patent as in the preceding case of Evans v. Eaton, and was argued by the same counsel. The points involved will be found to be fully discussed in the argument of that case, to which the learned reader is referred. The following is the charge delivered to the jury in the Court below, which it is thought necessary here to insert . . . (1.) Such as respect the value of the plaintiff’s Hopperboy. (2.) The time of its discovery. (3.) The kind of machine used by the defendant. (4.) The time of its discovery and use.”