27 
similar to the mottled sandstone, which I afterwards found 
occurred immediately under it. A third visit to the locality left 
no doubt upon the subject, for I discovered another quarry to the 
left of Euroclydon, the residence of Mr. Brary, (to whom I am 
indebted for valuable aid in the investigation of the rocks to 
which I am referring.) Near the top of this quarry was the 
mottled sandstone underlying the yellow bed before referred to, 
dipping at the same angle, and composed of grains averaging 
‘011 of an inch in diameter. Next in descending order was a 
yellow variegated sandstone of a more compact structure, the 
grains of which were less rounded, and in size measured about 
‘007 of an inch; then came a bed of a light grey tint with 
yellow patches here and there, and the grains averaging ‘004 of 
an inch in diameter. We here get a very good illustration of 
the change which was taking place in the elevation of the sea 
floor; a condition of things which ultimately allowed of the 
growth of that vegetation which gave rise to the Carboniferous 
coals. First we had a sea in which the Limestone was gradually 
formed; after a time the sea bottom was elevated, and the 
conditions became unfavourable to the life of those creatures 
which built up the Limestone. Sediment was brought down 
from the surrounding land by water agency, and deposited over 
the area. At first this sediment was very fine in size, but 
as the water became shallower the size increased. This is 
shown by glancing at the measurements of the grains which 
compose the beds of Millstone grit, and it will be observed that 
they become of larger dimensions as we pass upwards in the 
section. 
The examination of the quarry near Euroclydon enabled me 
to get the angle of dip of the beds, which I put at 40° and 
which it was impossible to ascertain in the railway cutting, 
though it was apparent that the angle was steep. In the 
section of the Carboniferous Limestone made by Messrs. Jones 
and Lucy, the dip is given as varying from 22° to 32%. Ina 
supplementary section kindly given me by Mr. Lucy, the dip of 
the beds higher up in the formation is put at 36°. If, therefore, 
we take Mr. Lucy’s angle of 36° for the Limestone, and mine 
