SUBJECT INDEX 



1187 



Magnetic (continued) 



vectors, 91, 186, 206, 214-218 



vertical intensity, 91, 92, 105, 106, 107, 113, 

 210-216 

 measurement of, 101, 102 

 Magnetisation: 



factors affecting, 167 



induced, 170 



intensity of, 75, 77, 79 



measurement of, 173 



remanent, 172 



residual, 170 



retentivity, 172 



terrestrial, 88 



Magnetometer, 99 



Airborne {see Mobil magnetometer) 

 Askania {see, Schmidt) 

 auxiliary magnets, 134, 136, 151 

 continuous recording, 144 

 field notes, calculation of, 149 



diurnal variation, 151 



latitude and longitude correction, 153 



temperature, 149 



time, 149 

 flux type (electromagnetic), 590 

 Gauss meter, 160 

 Hilger and Watts, 119, 120 

 Hotchkiss Superdip, 114-118 

 instrument adjustment, 147 

 instrument reading, 125, 126 

 Kohlrausch, 158 

 mobile magnetometer {see Mobile 



magnetometer) 

 orientation, 124 

 plotting data, 155 

 Ruska, 119 

 Schmidt type, horizontal, 118, 119, 120, 121 



auxiliary magnet, 134, 136 



instrument reading, 125, 126 



magnetic system, 121, 122 



orientation of, 124, 125 



scale value determination, 133, 134, 135, 148 



theory of, 129 

 Schmidt type, vertical, 118, 119, 121 



auxiliary magnet, 134, 136 



instrument reading, 125, 126 



magnetic system, 121, 122 



optical system, 123 



orientation of, 124, 125 



scale value determination, 131-135, 148 



temperature compensation of, 139 



temperature correction, 140 



temperature determination, 137, 138 



theory of, 127 

 shipborne, 224 

 station spacing, 155 

 suspension type, 589 

 Thalen-Tiberg, 113 

 Magnetometric method, 580 

 Magnetron, 103 

 Magnets, 65 

 bar, 69^79 

 bar magnetic force, 79, 80 



Magnets (continued) 



classification of, 62 



couples, 82, 85 



Gauss position I, 79, 83, 85 



Gauss position II, 80, 84, 86 



Gauss position III, 80, 87 



law of force, 67 



poles {see Magnetic, poles) 



properties of, 66, 74 

 Mapping: 



chemical soil analysis, 949, 954 



electrical, 574, 579 



gravitational, 415-425 



magnetic, 224, 231, 243 



radioactivity, 1008, 1009 



seismic, 738-750 

 Marker horizon, 766-769 

 Marsh buggy, 846, 847 

 Mechanical feed type drill, 878, 879 

 Mechanical samplers, 1083, 1084 

 Mechanical seismometers, 805-808 



Schwedar instrument, 805, 806 



Taylor instrument, 807 

 Mechano-transducer tube, 804, 805 

 Megger (ground tester), 541-545 

 Mendenhall pendulum, 275 

 Metamorphic rocks: 



density of, 264 



magnetic susceptibility of, 165 



velocity of, 660 

 Methane, 947, 948 

 Methods, Geophysical: 



applicability of, 35 



choice of, 32 



classification of, 20, 22 



cost of, 37 



electrical petroleum exploration, 31 



factors governing application and choice, 19 



gravitational petroleum exploration, 29 



in civil engineering, 56 



in mining, 42 



in water supply engineering, 56, 56 



magnetic petroleum exploration, 28 



modus opperandi, 23 



prospecting for petroleum, 27 



seismic petroleum exploration, 31 



technique of applying, 23 

 Mho, unit of conductivity, 1059 

 Micromagnetometer, 103 

 Minerals: 



density of, 264, 265 



magnetic properties, 160 



magnetic susceptibility of, 162, 164, 165 



resistivity, 441, 442 

 Mining: 



Act of 1872, 1144 



choice of methods, 44-46 



claims and options, 1144-1146 



classification of ore deposits, 46 



depth of geophysical application, 44 



geophysical methods in, 43-44 

 Mirragraph, 830-835 



