Existing comment:
The Boilers:
Three brick-encased boilers were originally installed on each side of the Engine House. The boilers were essentially long iron cylinders with a wood- or coal-burning furnace below which boiled water to make steam.
"[T]he power of the engines depends upon the quality of steam produced, and the degree to which it is heated, they might, by increasing the quantity and elastic power of the steam, be made to do the work of forty, fifty, or sixty horses each, without injury to the engines... Each of the large engines have three cylindrical boilers, each thirty inches in diameter, and twenty feet long. Each of the smaller engines have three cylindrical boilers thirty inches in diameter, and eighteen feet long; all the boilers are made of rolled iron, one-fourth of an inch thick."
-- Sylvester Welch, Report on the Allegheny Portage Railroad, 1833
The engine houses were originally equipped with two sets of three boilers. Despite Welch's assurances of the great horsepower generated by the boilers, they proved inefficient in hauling the heavy loads up the incline. In 1836, an additional boiler was installed on each side. |