Appellant applied for a patent on processes for testing milk and milk products by the use of acoustical principles previously known in relation to substances other than milk. The District Court reversed the Patent Office as to one claim asserted, finding it patentable, but held the subject matter of certain other claims unpatentable. This appeal is from the denial of claims 34 and 41 of the patent application.

We agree with the District Court that although these claims reflect important developments of substantial value to the industry, they do not meet the standards of invention under controlling decisions interpreting the applicable statute, 35 U.S.C. § 103 (1958). Darison Corp. v. Watson, D.C.D.C.1960, 182 F.Supp. 513; see Mandel Bros. v. Wallace, 1948, 335 U.S. 291, 69 S.Ct. 73, 93 L.Ed. 12; cf. L-O-F Glass Fibers Co. v. Watson, 1955, 97 U.S.App.D.C. 69, 228 F.2d 40; In re Dietert, 1957, 44 C.C.P.A. 808, 241 F.2d 746. Hence the judgment of the District Court must be

Affirmed.