Detroit Copper Mining Co. v. Mine & Smelter Supply Co.

(after stating the facts as above). [1] The appellants admit the validity of the Wilfley patent, but they contend that it covers an invention which is an extremely narrow improvement of an art which was old, and that since the invention described is for a specific improvement in that art, the claims are to be so limited as to apply closely to the apparatus described in the specifications and claims, since Wilfley patented as that feature of his invention only a specific form and arrangement of riffles, and a specific smooth surface upon the concentrating-table, and went no farther, and that when so construed the claims are not infringed by the appellants’ apparatus. The contention of the appellee is that the Wilfley invention marks a distinct advance, and discloses the application of principles and the performance of functions theretofore unknown to the art,- and that the claims thereof are entitled to a construction' commensurate with the step in advance, find that with such construction, and without expanding the Wilfley invention, the device used by the appellants will be found to infringe the same.

It is true that the use of concentrating-tables with riffles and with smooth…