PROF. J. BUCKMAN ON THE MIDFORD SANDS.
737
confounded two beds, in which he has been preceded and followed by the authors quoted.
The Cephalopoda-bed at Midford, Bradford Abbas, Halfway House, and Bridport is situated near the top of the Inferior Oolite, while the Cephalopoda-bed of Dr. Wright is situated at the bottom of that rock in Gloucestershire, and we have traces of this latter below the sands in Dorsetshire.
The so-called Midford Sands are the equivalents of the Ham-Hill building-stone, of the Doulting oolites, of the brown freestones and ragstones of the Cotteswolds, and of the grand sand section at Bridport Harbour.
In the accompanying diagram (fig. 1, p. 738) are placed side by side the Midford section and the Haresfield section.
The detailed section at Midford station is as follows in descending order:—
ft.
in.
1.
Soil and Bubble
................................................................................................................................................................................................................................................................................................................................................................................................
3
0
2.
Trigonia-Grit , consisting of irregular oolitic limestones with but few fossils
................................................................................................................................................................................................................................................................................................................................................................................................
12
0
3.
Gryphite-Grit =Cephalopoda-bed of Dorset, full of fossils, as at Bradford
................................................................................................................................................................................................................................................................................................................................................................................................
6
0
4.
Bed of hard sandy oolite=Dew bed of Bradford
................................................................................................................................................................................................................................................................................................................................................................................................
2
0
5.
Oolitic sands with occasional beds of sandy oolite seen on the line
................................................................................................................................................................................................................................................................................................................................................................................................
25
0
This bed to the bottom of the valley is nearly
................................................................................................................................................................................................................................................................................................................................................................................................
100
0
The detailed section at Haresfield Beacon:—
ft.
in.
Inferior Oolite of Glouestershire.
{
{\displaystyle \scriptstyle {\left\{{\begin{matrix}\ \\\\\ \\\ \\\ \\\ \\\ \\\ \\\ \\\ \\\ \\\ \\\ \\\ \\\ \\\ \\\ \ \end{matrix}}\right.}}
1.
Flaggy Beds=Trigonia-Grit
................................................................................................................................................................................................................................................................................................................................................................................................
4
0
2.
Soft Beds=Gryphite-Grit
................................................................................................................................................................................................................................................................................................................................................................................................
3
6
3.
Shelly beds
................................................................................................................................................................................................................................................................................................................................................................................................
}
{\displaystyle \scriptstyle {\left.{\begin{matrix}\ \\\ \end{matrix}}\right\}\,}}
}
{\displaystyle \scriptstyle {\left.{\begin{matrix}\ \\\\\ \ \end{matrix}}\right\}\,}}
Cephalopoda-beds of Cotteswolds
}
{\displaystyle \scriptstyle {\left.{\begin{matrix}\ \\\\\ \ \end{matrix}}\right\}\,}}
4.
Nodular Marl
................................................................................................................................................................................................................................................................................................................................................................................................
1
0
5.
Shelly beds
................................................................................................................................................................................................................................................................................................................................................................................................
2
0
6.
Oolitic Marl
................................................................................................................................................................................................................................................................................................................................................................................................
5
6
7.
Different freestone beds=the Midford sand 50 to
................................................................................................................................................................................................................................................................................................................................................................................................
70
0
8.
Sandstone
................................................................................................................................................................................................................................................................................................................................................................................................
1
6
9.
Ragstone, more or less oblique cleavage
................................................................................................................................................................................................................................................................................................................................................................................................
8
0
10.
Compact bed of stone
................................................................................................................................................................................................................................................................................................................................................................................................
2
6
11.
{
{\displaystyle \scriptstyle {\left\{{\begin{matrix}\ \\\\\ \ \end{matrix}}\right.}}
Two beds of soft Oolite, full of Cephalopoda, separated by a ferruginous band
................................................................................................................................................................................................................................................................................................................................................................................................
}
{\displaystyle \scriptstyle {\left.{\begin{matrix}\ \\\\\ \ \end{matrix}}\right\}\,}}
Upper Lias of Doctor Wright
}
{\displaystyle \scriptstyle {\left.{\begin{matrix}\ \\\\\ \ \end{matrix}}\right\}\,}}
2
4
12.
13.
Upper Lias.
{
{\displaystyle \scriptstyle {\left\{{\begin{matrix}\ \\\ \end{matrix}}\right.}}
14.
Sands and Arenaceous Marl of Upper Lias.
We take it, then, that the sections at Crickley Hill and Haresfield Beacon, in Gloucestershire, in their shelly oolites and ragstones, are the exact equivalents of at least 120 feet of the sands which at Midford and other places in Somerset, Bradford Abbas and Sherborne in Dorset, are identical.
These sands, as we have before shown, are interrupted by occasional beds of stone both at Midford and Bradford, which stones are usually as full of comminuted fossils as the shelly oolite of Leckhampton Hill; many of them, however, are capable of being identified, and the list to be given presently will show much the same fossils as occurring in both.