Ch. XXIV.] 



COAL— RAIN-PRINTS. 



489 



upon our taking a direction higher up or lower down the ancient river 

 or delta deposit. 



In the strata above described, the association of clays supporting 

 upright trees, with other beds containing brackish-water shells, implies 

 such a repeated change in the same area, from land to sea and from 

 sea to land, that here, if anywhere, we should expect to meet with 

 evidence of the fall of rain on ancient sea-beaches. Accordingly, rain- 

 prints were seen by Dr. Dawson and myself at various levels, but the 

 most perfect hitherto observed were discovered by Mr. Brown near 

 Sydney in Cape Breton. They consist of very delicate impressions 



Fiff. 542. 



Fiff. 543. 



Fig. 542. Carboniferous rain-prints •with worm-tracks (a, &) on green shale, from 



Cape Breton, Nova Scotia, Natural size. 

 Fig. 543. Casts of rain-prints on a portion of the same slab, fig. 542, seen on the under 



side of an incumbent layer of arenaceous shale. Natural size. 



The arrow represents the supposed direction of the shower. 



Fig. 544. 



Casts of carboniferous rain-prints and shrinkage-cracks (a) on the under side of a layer 

 of sandstone, Cape Breton, Nova Scotia. Natural size. 



of rain-drops on greenish slates, with several worm-tracks (a, b, fig. 

 .542), such as usually accompany rain-marks on the recent mud of the 

 Bay of Fundy, and other modern beaches. 



