| HILL'S MACHINE 1857 |
 |
| "Hill's machine
shows considerably more similarity with our modern
keyboard adding machines than either Parmelee's or
Schilt's device, yet it never advanced beyond the
experimental stage. The model illustrated may be found in
the National Museum in Washington." Ernst Martin, The
Calculating Machines. |
Photo is courtesy of: David Weil, Computer Museum of America. |