The SciencesInventions New and Interesting - September 11, 1915Simple Patent Law; Patent Office News; Notes on TrademarksBy Frank C. Perkins on September 11, 1915AdvertisementABOUT THE AUTHOR(S)Recent Articles by Frank C. PerkinsA Portable Gasoline Drag SawNovel Auto ReelGuide Carriage for Laying Large Sewage Concrete Pipes in Tunnels