A U.S. patent was issued, antedated to 29 Jul 1843, for a hand-cranked ice-cream freezer invented by Nancy M. Johnson (No. 3,254). In previous designs, the ice-cream mixture was held in an inner container, which vessel was itself was rotated within an outer container of ice and salt. Her invention was to add a vertical shaft with curved, perforated paddles within the inner vessel, and reaching nearly to its inside wall. Stirring in one direction would carry the the liquid or semi-fluid mass from the centre to the circumference. Turning in the opposite direction would scrape frozen material and carry it from the inner walls to the centre of the freezer. Thus fresh matter continuously reached the freezing surface.

Was created by the Radio Corporation of America (RCA), shortly after the acquistion (May 1926) of the radio network operations of AT&T, which had decided to withdraw from radio. The new NBC network was publicized with full-page ads in many publications. The new network's debut broadcast was transmitted on 15 Nov 1926. The network assets bought from AT&T with stations in major cities of several states became the NBC-Red network (a designation reflecting its origin when the inter-city circuit charts were marked with telephone links between network radio stations in red pencil. The smaller existing network of the buyer became NBC-Blue.