PROSPECTING INDICATOR.

Hawera Star, Volume XLVIII, 25 October 1924, Page 14

PROSPECTING INDICATOR.

SEEKING HIDDEN FORTUNES. Quite a number of inquiries havo been received by the Scientific American concerning an alleged prospecting indicator, by means of which the prospector had only to wander over the face of the earth carrying his machine in his hand and sticking in a peg wherever the device indicated a hidden fortune. It is a fact that several new prospecting methods have recently been developed, which depend on indicating devices. But the belief that anyone could use them to find ready gold anywhere it exists is, to. say tiie least, highly exaggerated. Canadian Mining Journal issue of April 25, 1924, describes quite sympathetically several now methods of locating minerals from the surface. One method is magnetic surveying, developed in Sweden. A dip needle is used; but it will indicate only magnetic and pyrrhotite. There are in addition two electrical methods of prospecting, one being based on the principle <;f spontaneous polarisation, metallic sulphides acted on by ground waters producing an electric ” current; the other, called the Lunberg-Nathorst system, being based on the greater electrical conductivity of sulphide ore bodies than the surrounding rock. In the first method the deposits must he above and one below the ground water level. The ore must also be within 300 feet of the surface, and both oxidising and reducing solutions must be present. Still another method is the Eotvos Torsion balance method, which is based on the difference in specific gravity of heavy and light frocks. None "of these methods is 1 simple, all requiring much geological training and technical knowledge for their successful use. Some of them have proved quite successful, but their limitations are so great that they are not a snap method of getting rich quick. Someone is always taking the joy out of life!