Referring to the [illustration of Felt’s first metal machine], it will be noted that the machine has been partly dismantled. The model was robbed of some of its parts to be used as samples for the manufacture of a lot of machines that were made later. In view of the fact that this machine is the first operative multiple-order key-driven calculating machine made, it seems a shame that it had to be so dismantled; but the remaining orders are operative and serve well to demonstrate the claims held for it.
Felt patent 371,496
The mechanism of the machine is illustrated in the reproduction of the [drawings of Felt’s patent, 371,496], on page 58. The specification of this patent shows that it was applied for in March, 1887, and issued October 11, 1887.
From the outward appearance of the machine it has the same general scheme of formation as is disclosed in the wooden model.
The First “Comptometer”
From Drawings of Felt Patent No. 371,496
Description of Felt calculator