(concurring). I concur in the result, but upon these grounds: Assuming, for the purpose of a preliminary injunction, that the patent is valid, as the court rightfully did (Electric Light Manuf'g Co. v. Edison Electric Light Co., 18 U. S. App. 637, 10 C. C. A. 106, and 61 Fed. 834), it still remained that, to warrant a preliminary injunction, the fact of infringement should be made out beyond reasonable doubt (Standard Elevator Co. v. Crane Elevator Co., 9 U. S. App. 556, 6 C. C. A. 100, and 56 Fed. 718). There is here so much of doubt with respect to the proper construction of the claims of the patent and of their infringement that it is needful to have an investigation into the prior art to determine the exact limitation of the claims, and to have “the searchlight of an intelligent cross-examination” to determine conclusively the fact of infringement.