Dubois v. Philadelphia, W. & B. R.

stopped the plaintiff’s counsel when about to reply, and said: I have no doubt of the application of the doctrine of estoppel to the case. There is no difference in this respect between this ease and any other. It is true the point is one that does not appear to have been decided in a patent cause; but, in the opinion of the court, that makes no difference. The principle involved is as applicable to patent cases as to any other cases. If it were not, there would be no end of litigation between the same parties. Every n'ew suit would be-met by a now defense. It was the purpose of the law to prevent this continued litigation. (The court referred to several authorities, and *1141particularly to the case of Beloit v. Morgan, 7 Wall. [74 U. S.] 619.)