51 
The Clay is found nearly all over the Cotteswold range, 
varying in thickness from a few inches to three feet, and often 
- occurring in pockets, but without any inequality in the surface 
of the land indicating the existence of small hollows prior 
to its deposition; and in many places where it could never 
have been levelled by cultivation. 
To begin with the Mickleton Tunnel, the summit of which is 
490 feet above sea level, and therefore not on the high plateau; 
but it is there that the greatest development of the Boulder- 
clay is met with, and I want to trace its course. The following 
Section is from Mr. Gavey’s paper, in the Quarterly Journal 
of the Geological Society, for 1853, and was made, it should 
be remembered, long before Ice action and Boulder-clay were 
thought of in connection with the Cotteswold district. (See 
drawing.) 
ft. in. ft. in. 
“« Vegetable Soil, about . 0 0 to 0 9 
Loamy Sand and Pebbles ; 5 0 «15 0 
Fine Loamys and passing into coarse 5 6 « 20 0 
Gravel and Clay aa ea ES 5 0 « 30 0 
Red Clay, with Boulders of Marlstone ee. AO ae CO 
Loose Shingle Gravel ce ae 1 0 «16 0 
Red Clay, with Boulders of Marlstone +e | ee 5 a) 
Lower Lias Shale, more than . 0 0 » 80 0” 
itr. Gavey says, “The loamy silicious gravel, sand, and red 
clay beds give an average thickness of about 76 feet, and the 
Red Clays are non-fossiliferous, but contain large detached 
blocks of Marlstone of a bluish colour and uneven fracture, 
and with edges considerably rounded by attrition, and they 
were from one hundred-weight to three tons each.” 
About a mile after leaving Tetbury, on the way to Malmesbury, 
in a level field on the left hand side, adjoining the road, is a 
small quarry with one and a half feet of Boulder-clay forming 
the subsoil. In the quarry is an opening or fissure shewing 
Clay fully six feet thick. My attention was drawn to this by 
my friend Mr. G. F. Prayye, and who also informed me that he 
had found Quartz Pebbles in a fissure of a large quarry close to 
Tetbury, the same from which Mr. Hotrorp is using the stone 
for the erection of his house. 
E 2 
