| 1920 LA MERE Railway Signal Patent Print Art |
| 1920 ANDRESS BERT Railway Signal Patent Print |
| 1920 POLLMILLER Semaphore Signal Patent Print |
| 1920 GENN Portable Signal Device Patent Print |
| 1920 LAWRENCE CURRIE Track Signal Patent Print |
| 1920 ERNEST RUBES Warning Signal Patent Print |
| 1920 OMRI TREANOR Signal Patent Print Art |
| 1920 MARSH SARGENT Detection Signal Patent Print |
| 1920 MARR JOHN Auto Theft Signal Patent Print |
| 1920 RODENBUR Signal Carrying Case Patent Print |
| 1920 KELLAM ERNEST Train Signal Patent Print Art |
| 1920 SMITH WILLIAM Railway Signal Patent Print |
| 1920 AUGUST MEYER Signal Lamp Patent Print Art |
| 1920 JOSEPH Bearing Wear Signal Art Print |
| 1920 MAGNETIC SIGNAL Electric Switch Art Print |
| 1920 MICHELS Railway Cab Signal Patent Print Art |
| 1920 WANKLYN FREDERIC Track Signal Patent Print |
| 1920 ERNEST SANDERS Car Door Signal Patent Print |
| 1920 LOUIS Automobile Theft Signal Patent Print |
| 1920 OSCAR Highway Crossing Signal Patent Print |
| 1920 HANDLAN Railway Signal Lamp Patent Print |
| 1920 JOHN EVANS Railway Signal Patent Print Art |