From "The Beasts of Tarzan" by Edgar Rice Burroughs
Upon the shore he found an out-cropping of brittle, igneous rock.
By dint of much labour he managed to chip off a narrow sliver some
twelve inches long by a quarter of an inch thick. One edge was
quite thin for a few inches near the tip. It was the rudiment of
With it he went into the jungle, searching until he found a fallen
tree of a certain species of hardwood with which he was familiar.
From this he cut a small straight branch, which he pointed at one
Then he scooped a small, round hole in the surface of the prostrate
trunk. Into this he crumbled a few bits of dry bark, minutely
shredded, after which he inserted the tip of his pointed stick,
and, sitting astride the bole of the tree, spun the slender rod
rapidly between his palms.
After a time a thin smoke rose from the little mass of tinder, and
a moment later the whole broke into flame. Heaping some larger
twigs and sticks upon the tiny fire, Tarzan soon had quite a
respectable blaze roaring in the enlarging cavity of the dead tree.
Into this he thrust the blade of his stone knife, and as it became
superheated he would withdraw it, touching a spot near the thin
edge with a drop of moisture. Beneath the wetted area a little
flake of the glassy material would crack and scale away.
Thus, very slowly, the ape-man commenced the tedious operation of
putting a thin edge upon his primitive hunting-knife.
He did not attempt to accomplish the feat all in one sitting.
At first he was content to achieve a cutting edge of a couple of
inches, with which he cut a long, pliable bow, a handle for his
knife, a stout cudgel, and a goodly supply of arrows.