ABSTRACT
For many centuries miners have been excavating below the ground surface in their ceaseless search for minerals. Originally, these underground operations were simply a downward extension of the small excavations created to exploit surface outcrops. As mineral exploration methods became more sophisticated, resulting in the discovery of large ore bodies at considerable depth below surface, under ground mining methods were developed to exploit these deposits. These new mining methods were evolved from hard won practical experience and one must admire the skill and courage of the mining pioneers whose only acknowledgement of the difficulties which they encountered was to admit that there were certain areas of "bad ground" in the nor mally "good ground" which they worked.
