In late autumn 1911, after a local businessman suggested that the names under which the rocks had been dedicated should be cut into them, D.M. Stahlman began inscribing a few rocks with a railroad spike before stopping for the winter. The following spring he resumed the work with a mason's point and a mallet, carving the names in large letters with double outlines, and Courage Rock was the first engraved in this manner because he believed courage would be the quality most needed as the work progressed. The freshly cut letters would have stood out sharply against the darker, grayer rock and likely attracted the attention of passersby, and his engravings were generally placed where people were most likely to encounter them. Long before Stahlman began carving, large amounts of rock had apparently been removed from the park for building stone, reflecting nineteenth-century quarrying for the stone foundations required by large construction. Courage Rock shows an excellent example of flat-wedge quarrying, in which the rock was first scored along the intended cut, then slotted with a cape chisel, and finally split by driving flat iron wedges and shims into the slots until the stone cracked in a straight line; the rock broke, and the cut stones remain in their original position. Other quarried rock in the park includes 100 Fold Rock, Coming Out Rock, and numerous depressions and piles of rock rubble marking places where stone was removed.