Gruber had made up a stereo imaging rig out of two Kodak Bantam Specials mounted together on a tripod. He designed a machine that mounted the tiny pieces of Kodachrome color transparency film into reels made from heavy paper stock. A special viewer was also designed and produced. He had the idea of updating the old-fashioned stereoscope by using the new Kodachrome 16-mm color film, which had recently become available. New business venture A View-Master reel holds 14 film transparencies in seven pairs, making up the seven stereoscopic images. The components of each pair are viewed simultaneously, one by each eye, thus simulating binocular depth perception. According to a 1960 court document, the Gruber-Sawyer partner venture began from that first meeting in 1938. Thereafter, Ed Mayer negotiated with Gruber while production methods and some marketing were developed. After three years, a formal agreement was entered into on February 24, 1942, between Gruber and Sawyer partners, doing business as Sawyer's. Ed Mayer and people within the Sawyer's organization were uncertain what to call their new product, but they eventually came up with the name "View-Master". The View-Master brand name eventually came to be recognized by 65 percent of the world's population, but William Gruber disliked the name which Mayer gave it, thinking that it sounded too much like Toast-Master, Mix-Master, or some other kitchen appliance. The View-Master was introduced at the 1939 New York World's Fair, marked "Patent Applied For". It was intended as an alternative to the scenic postcard, and was originally sold at photography shops, stationery stores, and scenic-attraction gift shops. The main subjects of View-Master reels were Carlsbad Caverns and the Grand Canyon. The View-Master was marketed through Ed Mayer's photo-finishing, postcard, and greeting card company Sawyer's Service, Inc., known eventually as Sawyer's, Inc. The partnership led to the retail sales of View-Master viewers and reels. The patent on the viewing device was issued in 1940, on what came to be called the Model A viewer. Within a very short time, the View-Master took over the postcard business at Sawyer's. Expansion Ed Mayer gave details of the company's expansion in a letter dated April 1, 1954: In 1939, 20 years after starting the business, we had, by dint of hard work and long hours and frugal living, accumulated a business (Sawyer's) worth about $58,000.00 and Western Photo Supply Co. owning the buildings, worth about $30,000.00. The above figures