"The sand had etched the glass... and revealed the contrast against parts... covered by steel mesh"
H. J. Plaster, A Tribute to Benjamin Chew Tilghman
Legend has it that Benjamin Chew Tilghman (1821-1901), when based in the desert with the U.S. Army, noticed the effect that windblown sand had on the windows of the army buildings, and developed his ideas on sandblasting from there. Tilghman proposed that grains of sand, or quartz, fired at high speed toward a hard surface would allow smoothing, shaping, cleaning, and engraving with greater accuracy and power than current methods.
Using compressed air, steam, or water to propel the grains, Tilghman was able to etch away at the surface of a substance harder than the grains themselves. Stone engraving was not new but Tilghman's system replaced the expensive and time- consuming process of hand-chiseling, allowing the user to create effects on any hard surface. From then on, sandblasting has been used to clean buildings, carve glass, and engrave stone.
Since 1870 one minor adjustment has been made to Tilghman's original design. The silica dust produced during the sandblasting process was often inhaled and caused silicosis—a potentially fatal lung disease. Now, other materials tend to be used instead of sand. These include steel shots, glass beads, dry ice, baking soda, and walnut shells. Safety measures such as proper ventilation have also been adopted.
