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The cable-operated excavator is the earliest documented self-powered machine ever used to move earth. Its earliest form, the steam shovel, has roots going back to the very first mechanical excavator, the Otis Steam Shovel of 1835. From this machine, the half-swinging "railroad shovel" was developed, its name derived from the fact that the early shovels were mounted on standard-gauge rail tracks, and most of the early shovel work was in railroad construction.
During the first 40 years after its invention, very few steam shovels were built. Labor was plentiful and the shovel patents were strictly held by the Otis family, who built them to gain advantage over competitors in their contracting business. When the Otis patents finally expired in the 1870s, several other companies began building steam shovels, one of which was the Vulcan Iron Works Co. of Toledo, Ohio, established in 1870. From the early 1880s, this company contracted to build steam shovels to the designs of Mr. H.T. Stock, an old-time shovel operator and designer, but in 1986 began building its own line of steam shovels branded with the name "Giant."
One of the most popular Vulcan steam shovels was the "Little Giant." Usually mounted on traction wheels as shown in the illustration, it was used for generally lighter duties than the larger rail-mounted models. Its 7-inch-bore by 11-inch-stroke main engines provided 40 horsepower, and operating weight was quoted at 35 tons. Its vertical steam boiler was 48 inches in diameter and 7 feet 6 inches in height. Dipper capacity was 1¼ cubic yards, and its 17-foot boom provided a dumping height of 10 feet. The car on which it was mounted measured 23 feet long by 7 feet wide.
The Vulcan Little Giant shovel was typical of early railroad shovels, consisting of a steel or wooden house mounted on a rail car which supported the draw works, boiler, and swinging boom. The boom, mounted on one end of the car, was capable of swinging approximately 180 degrees.
It took a sizable crew to keep those old shovels running. As well as operator, cranesman and fireman, a two or three-man ground crew looked after the supporting timbers or rails on which those heavy machines moved. The cranesman's duties in-cluded operating the clutch and brake for the boom-mounted crowd engine, and opening the dipper door at the correct moment by pulling on a rope. He stood on a platform on the boom, and absolute coordination was demanded by the operator who controlled the shovel hoisting and swinging functions.
The Vulcan line successfully expanded, and by 1909, covered shovels ranging from 15 to 120 tons including some of the largest at the time. In 1911, shovel manufacturer Bucyrus Co. took over manufacturing rights and shovel patents of the Vulcan Steam Shovel Co. Within a few years, the Vulcan designs were incorporated into the Bucyrus machines.
You can read more about the evolution of construction equipment in Keith Haddock's latest book release, an updated version of his fully illustrated Earthmover Encyclopedia now available in bookstores. Also, consider a membership in the Historical Construction Equipment Association, www.hcea.net.
