177 
the proper usages of modern mining engineering, and conse- 
quently were untenable; but it was with the greatest difficulty 
that the legal gentlemen, as well as the arbitrator, were at last 
convinced that difference in the angles of depression and con- 
tortions of the strata, such as those which occurred at St. 
Annals Iron Mine, could affect the boundary lines of iron mines 
in the Forest of Dean. 
The sectional headings, a, a’, and a”, in the Oakwood Iron 
Mine are identical, but might occupy either of these positions 
as indicated laterally in the same mine, depending upon the 
variable angle of depression of the strata. The same remark 
holds good with reference to the heading 5, b’, and b” in the 
Parkhill Level Iron Mine. 
