With Solomon Willard’s well-rendered isometric drawing of each stone for a guide, the stonecutter dressed it, first selecting the best face for the “bed” (bottom) and hammered it to a plane surface, determined by shallow channels (chisel drafts) cut diagonally across the stone.
From this surface, the stonecutter laid out the other faces, including the “build” (top), by his good mason’s square or template. The texture of the visible face was “tooled,” that is, the marks of the chisel remained visible. Quincy granite is a quality product, taking a high polish, but the builders of the Bunker Hill Monument desired no polish on their monument. Today, the surface of the monument shows faint, well-weathered lines, like those produced by the modern bushhammer, which has a head made of several thin steel plates bolted together, each sharpened to a cutting edge. In England during the period, flat iron bars with rough edges were in use to saw softer stone than granite, and at Quincy, Willard experimented with dressing machines. The conclusion may be drawn, however, that the stones which we now see on the monument were undoubtedly shaped to their present dimensions by hand.
Today, 110 years after its capstone was put in place, the Bunker Hill Monument stands as an impressive testimonial to the conservative judgment of its designer, Loammi Baldwin, and the painstaking fidelity of the man who supervised its construction, Solomon Willard. An engineer familiar with its maintenance states that there is no evidence of settlement, and that a check by surveyor’s transit revealed no signs of misalignment. Its joints occasionally need pointing, the last pointing being performed about 20 years ago. Various iron or steel members of the observation chamber have had to be replaced. Its lightning rod has been in place for many years, but there is no readily available record to check whether the monument has ever been struck by lightning. With their empirical methods of design and their crude, mostly hand-operated, construction apparatus, our forebears built a sturdy structure, which, barring an earthquake, should last for centuries.
The Granite Railway
On 7 October 1826, the first railroad in America started operation. This was the horse-operated Granite Railway, built to transport the stones for the Bunker Hill Monument from the quarry in Quincy down to the Neponset River, a distance of nearly three miles. The track and cars of the railroad had been designed and built by a young engineer of 28, Gridley Bryant, whose Granite Railway project started him on a long career of achievement in the invention of equipment that played a major part in the rapid and successful development of the American railroad system.
Ample precedent for the Granite Railway existed in England, where, since the reign of Charles II, wooden tracks, sometimes armored with iron plates, had been used as runways for coal cars from the pits to the nearest waterway. Within five years of the start of the Granite Railway, similar systems are recorded in the states of Pennsylvania, South Carolina, New York, and Maryland. At first, the motive power for these lines was supplied by gravity, stationary engines, or horses, but soon tiny steam locomotives were tried. Thus, in the year 1829, Peter Cooper built the famous Tom Thumb, a successful locomotive which used rifle barrels for flues. In the same year the Stourbridge Lion, “the first locomotive that ever turned a driving wheel on a railroad on the Western Continent,”[7] was brought by sailing vessel from England and started operation in Pennsylvania. The American steam railroad system was thus well under way by the time the lower courses of the monument were being raised.
[7] Annual Report of the Smithsonian Institution, 1889.
Bryant later described his railroad as having stone sleepers laid across the track, 8 feet apart. Upon these, were placed wooden rails, 6 inches thick and 12 inches high (replaced by stone within a few years). Spiked on top of these were iron plates, 3 inches wide by ¼ inch thick. However, at road crossings, stone rails were used, with 4-inch by ½-inch iron plates bolted on top. This “permanent” construction was also used on the double-track, inclined plane at the quarry. (Well-preserved vestiges of this “permanent” construction are visible today at the rise to the Bunker Hill Quarry.) Here, an endless chain allowed the loaded, descending cars to pull up the empty ascending ones.
The standard gauge of American railroads is now 4 feet, 8½ inches, measured between railheads, a standard adopted after many years of confusion before the present gauge dimension was adopted. Although Bryant described his track gauge as 5 feet, this dimension was measured between the “bearing points” of the wheels on the tracks. If the bearing points are assumed to be the center of the treads of the wheels, his gauge is found to match closely the present standard gauge. This track gauge agrees with that adopted by the famous English railroad engineer, George Stephenson, at about the same time, after he had measured scores of carts used by his farmer neighbors. Possibly, both Stephenson and Bryant knew that their selected gauge had a very early beginning; for some historians suggest that the English carts were originally made to fit the ruts cut in the roads of Britain by the Roman chariots, many centuries earlier, during the Roman occupation of Britain.
On the day when the railroad started operation, 16 tons of granite from the Bunker Hill Quarry, and loaded on three “wagons,” were easily pulled by one horse, once started. Bryant’s first car had flanged wheels, 6½ feet in diameter, from the axles of which a platform was hung to carry the granite. This platform was lowered to receive the load and then raised by an ingenious gearing device.