Yorke Peninsula lies between Spencer Gulf and Gulf St. Vincent. As its discoverer Matthew Flinders-wrote: "it is singular in its form, bearing some resemblance to a very ill-shaped leg and foot". This Bulletin deals with an area having an arbitrary boundary along the northern edge of the Wallaroo one-mile sheet (Lat. 33 degrees 45' S.), only passing reference being' made to the area to the north, most of which is masked by sand. Reference is necessarily made to the northeastern area on part of the Blyth and Wakefield one mile sheets. The northwestern part of the peninsula was for many years an important copper-mining area. Here were the famous Wallaroo and Moonta copper mines; discovered in 1860 and finally abandoned in 1923. The towns of Moonta and Kadina grew around these mines and Wallaroo developed as a port with smelters