electric, etc., signal 00. v. hall, etc., signal co. 608 Electric -Eaileoad Signal Co. v. Hall Eailroad Signal Go. �(Circuit Court, D. Connectieut. April 5, 1881.) �1. Invention— Pbioeity. �He who flrst reduces his invention to a fixed, positive, and praoti- cai form would seem to be entitled to a priority of right to a patent therefor. 3. Same— Samb. �In such case, however, he who invents flrst has the prior right, if he uses reasonable diligence in adapting and perfecting the same, although the second inventer has, in fact, flrst perfected the same and rednced the same to practice in a positive form. �3. Same — Samb— Diligence. �In such case the determination of the fact of diligence is not to he reached by a comparison of the diligence of the two inventera. �4. Samb— Sajib— Same. �A. mentally -vvorked out an invention about November 6, 1872, and, ■without maklng any efforts to reduce the invention to practice,^ applied for a patent May 15, 1873. B. Independently reached the same resuit about December 21, 1872, and reduced the invention to practice in April, 1873. Held, where a patent was subsequently granted to A., that B. could not be held liable as an infringer for the use of this invention. — [Ed. �Charles E, Perk'ms and Franklin Chamherlin, for plaintiffs. �Simeon E. Baldwin, for defendant. �Shipman, D. J. This is a bill in equity to restrain the defendant from the alleged infringement of letters patent No. 140,536, issued to Frank L. Pope on July 1, 1873, and now owned by the plaintiffs, for improvements in circuits for electric railroad signais. Before the date of this invention eleetro-magnetism had been utilized for the automatic actua- tion of signais, denoting both danger and safety upon the line of a railroad. By Johnson's patent of 1858 a single battery ■was mounted on each train, and was applied to turn the sig- nais in succession. Each signal was operated alternately by two electro magnats; one to turn it to "danger," and the other to turn it to "safety." This plan required a battery for each train. Under Clark's patent of 1861 the signais were operated by the action of a railroad train ; but his apparatus made use of a special battery, and an independent electric ��� �
