A word as to the formation of caves, grottoes, caverns, and rock shelters.
But the man was staring beyond the little column of rock shelters.
The rock shelters are shallow, or with a thin covering of earth on the floor, or subject to overflow.
The cave and rock shelters of Bruniquel (Tarn-et-Garonne) have been carefully examined by competent explorers.
Many of the text illustrations ...