IN this contribution to the Institute Proceedings particulars are furnished of various special developments in electrical power practice applied to the Broken Hill mining service. These are described in a form to meet the interest of members of the Australasian Institute of Mining and Metallurgy as mining men, and will possibly be of value to mining engineers who are not experts on electrical power applications, but who, nevertheless are interested in such developments affecting the utility and advantages of electrical power relating to Broken Hill conditions and mining fields generally. This paper is not intended to be a comprehensive or technical thesis on electrical power generally, as applied to the Broken Hill mines, nor is it a full detail of electrical applications in the many forms and varied duties operating on the South mine in particular. The subject would demand a much more lengthy and technical paper to deal fully with the matter, and would be more appropriate for reading before an Institute of Electrical and Mechanical Engineers.