Elements of geology, or, The Elements of geology, or, The ancient changes of the earth and its inhabitants as illustrated by geological monuments elementsofgeolog00lyel Year: 1868 508 â FOOTPRINTS OF [Ch. XXV. which is represented in the foregoing drawing (fig. 559). It dis- plays, together with footprints, the casts of cracks (a, a!) of various sizes. The origin of such cracks in clay, and casts of the same, has before been explained, and referred to the drying and shrinking of mud, and the subsequent pouring of sand into open crevices. It will be seen that some of the cracks, as at b, c, tr
Elements of geology, or, The Elements of geology, or, The ancient changes of the earth and its inhabitants as illustrated by geological monuments elementsofgeolog00lyel Year: 1868 508 â FOOTPRINTS OF [Ch. XXV. which is represented in the foregoing drawing (fig. 559). It dis- plays, together with footprints, the casts of cracks (a, a!) of various sizes. The origin of such cracks in clay, and casts of the same, has before been explained, and referred to the drying and shrinking of mud, and the subsequent pouring of sand into open crevices. It will be seen that some of the cracks, as at b, c, traverse the footprints, and produce distortion in them, as might have been expected, for the mud must have been soft when the animal walked over it and left Fie. 560. Series of reptilian footprints in the coal-strata of Westmoreland County, Pennsylvania. a. Mark of nail ?
Size: 1065px × 1878px
Photo credit: © Bookworm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: archive, book, drawing, historical, history, illustration, image, page, picture, print, reference, vintage
