At any mine where one of the two openings as required herein, is a slope and is used as a traveling way, it shall not have a greater angle of descent than twenty degrees (20o) and may be of any depth. R.L.1910, § 3965.
Oklahoma Legal Code
At any mine where one of the two openings as required herein, is a slope and is used as a traveling way, it shall not have a greater angle of descent than twenty degrees (20o) and may be of any depth. R.L.1910, § 3965.