It is formed in strata of Old Red Sandstone, volcanic tufa, ignis fatuus, and bicarbonate of hornblende, superimposed upon argillaceous shale, and contains the prints of prehistoric man.
(It; is formed; L:in strata of Old Red Sandstone) (superimposed upon argillaceous shale; contains; the prints of prehistoric man)
It superimposed upon argillaceous shale
is formed contains
L:in strata of Old Red Sandstone
the prints of prehistoric man