Notes: "The Gray Arithmometer Co. of Ithaca, New York started selling the Gray Pocket Arithmometer, invented by James Gray, in the early 1920’s. It was distributed by the Morse Chain Company. The Gray is in most ways a common Kummer or Troncet type slide adder, but it implements subtraction by using a sliding gate that moves the “hook” from the top of the slides to the bottom. You may have noticed the Gray has a strong resemblance to the much more common Tasco Pocket Arithmometer. This is no accident. In 1929 the Morse Chain Company became part of Borg-Warner Corporation, and distribution of the Gray Arithmometer shifted to Tavella Sales Company. That is presumably when the name of the adder was changed to TASCO: TAvella Sales COmpany. This Tasco has no connection to the Tasco that sells imported telescopes and binoculars, which was originally Tanross Supply Co. There are several small differences between Gray and Tasco adders, but these are all minor changes that could be expected in a product that was made for at least 30 years. Consumers’ Research Bulletin, a predecessor of Consumer Reports, tested the Tasco in 1949 and rated it “Not Recommended”! They considered the construction quality “altogether unsatisfactory.” "
