| 1928 GILSON Railway Traffic Controlling Art |
| 1928 UNION Railway Traffic Controlling Art |
| 1928 MCCANN Railway Traffic Controlling Art |
| 1928 SINGER MFG CO Thread Controlling Device Art |
| 1928 LUCAS Railway Traffic Controlling Art |
| 1928 GRONDAHL Railway Traffic Controlling Art |
| 1928 UNION Thread Controlling Mechanism Sewing Machines |
| 1928 CARD Sewing Machine Needle Controlling Mechanism |
| 1928 THOMPSON Railway Traffic Controlling Art |
| 1928 SNAVELY Railway Traffic Controlling Art |
| 1928 SINGER Sewing Machine Needle Controlling Mechanism |
| 1928 WOLFGANG Train Controlling Means By Light Rays |
| 1928 BEALL Railway Traffic Controlling Art |
| 1928 LORENZ Train Controlling Means By Light Rays |
| 1928 ZIERDT Railway Traffic Controlling Art |
| 1928 SKENE Railway Traffic Controlling Art |
| 1928 FIFIELD Thread Controlling Device Patent |
| 1928 ACKERLY Railway Traffic Controlling Art |
| 1928 FAILOR Railway Traffic Controlling Art |
| 1928 LEE Railway Traffic Controlling Art Print |
| 1928 SMITH Railway Traffic Controlling Art |
| 1928 BAUGHMAN Railway Traffic Controlling Art |
| 1928 ALLEN Railway Traffic Controlling Art |