Court of Appeals for the Eighth Circuit August 2, 1897, No. 799 (Mast, Foos & Co. v. Dempster Mill Manuf'g Co.)

lead-opinion

SANBORN, Circuit Judge,

after stating the case as above, delivered the opinion of the court.

The court below dismissed the bill in this case on the ground that the statement contained in the letters patent upon which this suit is based, that “the invention is in practical operation, and on the market in considerable numbers, and the facts here stated with regard to its operation are