Machine Tracking
Tracking specific features of different machine models allows one to understand when changes were made to the production. For instance, the early Class 8 and 9 portable adding machines started out with a single screw holding the front of the case to the base of the machine. At some point, the designers decided that two screws, one on each side, made more sense. So the change was made, but the history of when it was made is hard to determine. So tracking hundreds of machines allows us to know that by 1927, almost all of the production with a single screw was finished.
Another example if the subtract mechanism on the Class 9 portable adders. It was a lever until about 1940 on manually operated machines. The details also show that electric machines had a subtract button well before all machines migrated from the level to the button.
Many other details are available to the sharp eye in the records attached here. Currently there are almost 900 machines data that has been included.
Another example if the subtract mechanism on the Class 9 portable adders. It was a lever until about 1940 on manually operated machines. The details also show that electric machines had a subtract button well before all machines migrated from the level to the button.
Many other details are available to the sharp eye in the records attached here. Currently there are almost 900 machines data that has been included.
| adder_records_of_1399_machines_v57.xlsx |