Superman (1939). Certain materials such as lead can block his X-ray vision. Superman can project beams of heat from his eyes which are hot enough to melt steel. He first used this power in "Superman" #59 (1949) by applying his X-ray vision at its highest intensity. In later stories, this ability is simply called "heat vision". Superman can hear sounds that are too faint for a human to hear, and at frequencies outside the human hearing range. This ability is introduced in "Action Comics" #11 (1939). "Action Comics" #1 (1938) explained that Superman's strength was common to all Kryptonians because they
Superman Siegel and Shuster were, at the time, negotiating a deal with the McClure Newspaper Syndicate for Superman. In early January, Siegel had a three-way telephone conversation with Liebowitz and an employee of McClure named Max Gaines. Gaines informed Siegel that McClure had rejected Superman, and asked if he could forward their Superman strips to Liebowitz so that Liebowitz could consider them for "Action Comics". Siegel agreed. Liebowitz and his colleagues were impressed by the strips, and they asked Siegel and Shuster to develop the strips into 13 pages for "Action Comics". Having grown tired of rejections, Siegel and Shuster accepted