Stereoview Card  “Sawing Marble - Ten Ton Block Direct from
Quarry, Proctor, Vermont”

History

In letter dated 1792 from Nathaniel Chapman to General Philip Schuyler is the first record discussion of sawing stone in United States. In 1793, a second discussion of the subject sawing stone appears an advertisement for the sale of quarry in Pennsylvania which suggests that property for sale was ideal for the erection of a mill for that purpose. By 1798, the New York firm of “Ricketts & Miles, Sculptors and Marble Merchants” makes the first mention of mills associated with a quarrying operation. Presumably these were mills for sawing. Pennsylvania had a sawing mill by 1798, Vermont had an operational mill circa 1808, and in Massachusetts an operation mill for sawing marble was advertised for sale in 1810.

One of the critical technological innovations in the development of sawing mills was the introduction of the gang saw. Basically, the gang saw was composed of multiple saw blades rather than a single blade. Previously, saw mills for cutting timber had always used a single blade. This work fine for a material like wood which cuts rapidly. However, sawing through a single block of stone is long and time consuming process. Having multiple blades sawing all at the same time meant the block of marble or soapstone could be sliced into slabs in a single sawing session. The earliest documented use of the gang saw technology is in Montreal Canada in 1804.

Process

The basic technique for sawing stone has been known since ancient times. A slurry of water and sand is fed between a flat toothless metal blade (copper or iron) and the blade is moved back and forth. The blade grinds the sand against the surface of the stone slowly wearing a narrow channel in the stone. The mills mounded the blades in horizontal frameworks. The blades could be reposition to adjust the width of the slabs being cut. The horizontal framework had four overhead swing arms which swung the framework back and forth. This setup was attached to a gear water powered mechanism which provide the power to move it. Overhead,

a sand and water dispensing mechanism was mounted. It provide a constant supply of slurry to the blades. The process was fairly automated and only required a few mill operators to monitor the saws.

In the 1880’s, William Ripley invented a automatic sand feed which collected the slurry below the mechanism, washed it, and recycled it to the dispenser on the top of the mechanism. It improved the efficiency of the operation and became the industrial standard of the times (source: History of Rutland County Vermont ... 1886).

This Italian advertising tradecard (circa 1900) illustrates the gang saw technology well. The basic swing arm design has not changed since it was first used in the early 1800’s.

Illustration from In the Marble Hills Century Magazine Vol. 40 No. 5  September 1890 pp. 743-751