
    Robert C. SWITZER, Appellant, v. Robert C. WATSON, Commissioner of Patents, Appellee.
    No. 13948.
    United States Court of Appeals District of Columbia Circuit.
    Argued Dec. 17, 1957.
    Decided Jan. 9, 1958.
    Mr. Albert L. Ely, Jr., Cleveland, Ohio, for appellant. Messrs. Roberts B. Lar-' son and Andrew E. Taylor, Washington, D. C., also entered appearances for appellant.
    Mr. Joseph Schimmel, Atty., United States Patent Office, with whom Mr. Clarence W. Moore, Sol., United States Patent Office, was on the brief, for appellee.
    Before Prettyman, Fahy and Bastían, Circuit Judges.
   PER CURIAM.

This is an appeal from a judgment of the District Court denying, after a trial de novo under 35 U.S.C. § 145, patentability of a visible penetrant method of non-destructive testing, a method by which the existence and location of minute cracks and flaws may be readily detected. The ground for the denial in the District Court was that the subject matter of the claims was nonpatentable over prior art and patents, and, in the case of one of the claims (No. 11), unpatentable on the ground of double patenting. The Primary Examiner and the Board of Patent Appeals had reached the same conclusion.

An examination of the record discloses, no error which would warrant disturbing the findings of the District Court. See Standard Oil Development Co. v. Marzall, 1950, 86 U.S.App.D.C. 210, 181 F.2d 280; Esso Standard Oil Co. v. Sun Oil Co., 1956, 97 U.S.App.D.C. 154, 229 F.2d 37.

Affirmed. 
      
      . Cf. Application of Ward, Cust. & Pat.App.1956, 236 F.2d 428.
     