d in a semicircle would be cheaper to construct and easier to maintain. His plan was to build a large rack of many small mirrors and adjust each one to reflect sunlight in a specific direction. To track the sun's movement, the entire rack could be rolled around a semicircular track, projecting the concentrated radiation onto a stationary boiler. The rack could be attended by a laborer and would have to be moved only "three or four times during the day," Adams noted, or more frequently to improve performance.Confident of his innovative arrangement, Adams began construction in late 1878. By gradually adding 17-by-10-inch flat mirrors and measuring the rising temperatures, he calculated that to generate the 1,200 F necessary to produce steam pressures high enough to operate conventional engines, the reflector would require 72 mirrors. To demonstrate the power of the concentrated radiation, Adams placed a piece of wood in the focus of the mirrored panes where, he noted, "it ignited immediately." He then arranged the collectors around a boiler, retaining Mouchout's enclosed cauldron configuration, and connected it to a 2.5-horsepower steam engine that operated during daylight hours "for a fortnight in the compound of [his] bungalow."Eager to display his invention, Adams notified newspapers and invited his important friends--including the Army's commander in chief, a colonel from the Royal Engineers, the secretary of public works, various justices, and principal mill owners--to a demonstration. Adams wrote that all were impressed, even the local engineers who, while doubtful that solar power could compete directly with coal and wood, thought it could be a practical supplemental energy source.Adams's experimentation ended soon after the demonstration, though, perhaps because he had achieved his goal of proving the feasibility of his basic design, but more likely because, as some say, he lacked sufficient entrepreneurial drive. Even so, his leg...
