from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Drawing, writing or inscription on stone, as a painting on a cave wall.
from The Century Dictionary and Cyclopedia
- n. A writing on a rock; a petroglyph.
“diviner,” and the Noguchi petrograph, which have now made, so to speak, hidden things visible to a depth of twenty-five miles, and there too he will find a description of a score of ingenious devices for isolating blocks of deep-lying rock and bringing their desirable ingredients to the surface.