Keywords: Fire-Alarm System 1852.jpg en William Francis Channing 1820-1901 Fire-Alarm System 1852 invention 1852-01-01 http //www nejm org/doi/full/10 1056/NEJM196209062671010 author other versions PD-old-70-1923 William Francis Channing Fire alarms Uploaded with UploadWizard Uploaded with UploadWizard |