| 1921 HENRY Spool Shifting Mechanism Patent Print |
| 1921 BLAKE Dumping Mechanism For Trucks Patent |
| 1921 CHARLES Breech Block Mechanism Patent Print |
| 1921 EDWARD Power Driving Mechanism Canal Other Barges |
| 1921 GEORGE Driving Mechanism Sewing Machines Like |
| 1921 SAMUEL Driving Mechanism Locomotives Art |
| 1921 HILLS HARRY Hoisting Mechanism Patent Print |
| 1921 HUDSON Method Mechanism Exploding Submarine Mines |
| 1921 DYER Elevating Mechanism Shop Trucks Art |
| 1921 KENNEDY Steering Mechanism Dirigible Bodies |
| 1921 ALBURY Automatic Stop Mechanism Railroads |
| 1921 JAMES Propelling Mechanism Vessels Art |
| 1921 ERNST Gate Operating Mechanism Patent Print |
| 1921 ELBERT Trigger Sear Mechanism Machine Guns |
| 1921 BLACKBURN Indicating Mechanism Game Art |
| 1921 LEONARD Hydraulic Operating Mechanism Valves |
| 1921 HERBERT Ejector Mechanism Drop Down Guns |
| 1921 JOHN WHITE Ejector Mechanism Drop Down Guns |
| 1921 HOLMES Recoil Mechanism For Guns Patent |
| 1921 BROWN Controlling Mechanism Booster Motors |