"Drill hole" Quotes from Famous Books
 ... and such abandoned, mine cannot be explored, or when same contains fire-damp, or water which may inundate such working place, the mine-foreman shall not permit such working place to be advanced until a drill hole has been extended not less than twelve feet in the center of such working place, and a flank hole not less than twelve feet extended on each rib, starting at the working place after taking out each cut or crossing. ...
— Mining Laws of Ohio, 1921 • Anonymous |
