Vintage Comptometer Adding Calculator Machine Felt & Tarrant MJG Co Chicago

Description

Vintage Comptometer Adding Calculator Machine Felt & Tarrant MJG Co Chicago.
The Comptometer was the first successful key driven adding and calculating machine. "Key driven" means that just pressing the keys adds the numbers entered to the total - no other action is required - so it is very quick for adding long lists of numbers. The basic function of the Comptometer is addition. There is a column of keys (in general 1-9) for each decade. When a key is pressed, that number is added to that decade, with carry to the next higher decade, if applicable. Pulling the lever forwards clears the total to zero.
This machine is in amazing condition for its age and is in working order.
Has a beautiful patina from the age, and all the original keys are still intact. The lever is smooth functioning and the keys all work well.
Please refer to photos as they are part of the description.
Love from Lawrence and Sally of Baggage Battles and Storage Wars.