976 



SUBJECT INDEX 



Faults, 5, 8, 15, 29, 35, 43, 45, 46, 52, 53, 

 61, 63, 70, 151, 152, 252, 264, 284- 

 286, 296, 395, 396, 425-427, 430, 432, 

 433, 441, 514-517, 519, 520, 624, 625, 

 718-721, 735, 738, 739, 742, 748-752, 

 754-756, 774, 805, 815, 853, 855, 862, 

 865, 870, 875, 883-885 

 Fechner balance, 193 

 Fechner pendulum, 109 

 Feldspar, 55 

 density of -, 80 

 elastic moduli of -, 467 

 heat conductivity of -, 848 

 specific heat of -, 848 

 Fence, magnetic effect of, 373 

 Fermat's principle, 504, 533, 534 

 Ferromagnetic substances, 317. 

 Field balance {see Magnetometer, 



Schmidt) 

 Field strength (see Electrical fields, 

 Electromagnetic fields, and Mag- 

 netic fields) 

 Fields, physical: 

 direction of-, 39, 88, 89, 168,289,621,626 

 potential of - (see also Potential), 39 

 quasi-stationary -, 38, 681 

 stationary -, 38, 88, 293, 681-684 

 variation of -, with time, 38, 162-167 

 Figure eight, 684, 688 

 Fisher Metallascope, 628, 823, 824 

 Fish shoals, 64, 956, 957 

 Fissures (see also Faults), 60, 61, 427, 

 623, 738, 739, 870, 875, 883-885, 904- 

 907, 909, 928-930, 933 

 Flank formations, 274, 276, 296, 422, 423, 



862 

 Flash box, 105, 109, 117, 120 

 Flattening, 95, 96, 97, 212 

 Flexure : 



- of pendulum support, 101, 121 



- correction, 119-122. 

 Flint, density of, 80 

 Float, 703. 



magnetic effect of -, 376 

 Floats, measurements on, 41, 42 

 Flotation method, 72 

 Fluctuation (see Variation) 

 Fluid level determination, 867, 936, 942, 



943 

 Fluorite: 



density of -, 79 



- deposits, 50 



electrical location of -, 52, 55, 735, 739 



heat conductivity of -, 848 

 Fluorspar (see Fluorite) 

 Flux, magnetic, 298, 299, 360, 596 



electrical -, 26, 27,^1 

 Flywheel machines (see Vibrators) 

 Focal length, 178, 194, 321-323, 327, 328, 



335-337, 340, 341, 344, 600, 608 

 Focal plane, 115 

 Focus, 106 

 Folding, 317, 551 



Folds {see Anticlines) 



Fontactometer, 881 



Forced oscillations, 36, 62, 461, 481, 586- 



911, 912, 917-919 

 Formation boundaries: 

 concentration differences on -, 622, 



631, 667, 678, 679, 831-833 

 density contrasts on -, 10, 67, 148, 278, 



283, 285 

 differences in elasticity on-, 439, 441, 



475, 478, 504, 548 

 differences in heat conductivity on -, 



851. 

 differences of magnetization on-, 296, 



390, 395, 425 

 resistivity contrasts on -, 28, 33, 622, 

 698-700, 712, 718, 742, 765, 797, 828, 

 829 

 Formation water (see Water) 

 Foundation studies, 6, 8, 57, 58, 435, 441, 

 624, 625, 733, 741, 742, 911, 913, 

 914, 922, 928-930, 933. 

 Four-electrode methods (see Resis- 

 tivity methods and Gish-Rooney 

 method) 

 Fourier series, 220, 222 

 Fractional distillation, 891 

 Fractionation, low-temperature, 892, 



898, 900 

 Fracture zones (see Shear zones) 

 Frame, detection (see Coil, reception) 

 Franklinite: 

 density of -, 78 

 susceptibility of -, 310 

 Free-air correction, 135-137, 141 

 Free fall in vacuum, 123 

 Free oscillations, 62, 86, 97, 100, 356, 449, 

 461, 582-586, 598, 615, 616, 911-914 

 Freezing method of shaft sinking, 867 

 Frequency (ies): 

 acoustic -, 866, 937, 940, 941, 945, 946, 



949, 952, 953, 955, 958 

 angular -, 92-100, 124, 449, 581-584, 

 639-641, 688 



- bridge, 647, 774 



damped (seismic) -, 584, 585, 588, 601 



- and depth penetration of electric 



current (see Depth penetration) 



- factor, 587, 588, 604-606. 919 

 ground- (seismic) ^, 452, 586-590, 593- 



596, 598, 601-607, 911-913, 915, 920. 

 high (electric) -, 619, 622, 623, 648, 685, 



774, 805-809, 819, 821-823, 867 

 intermediate (electric) -, 619, 646, 647, 



774 

 low (electric) -, 619, 645-646, 766, 774, 



780, 797, 819, 823 

 natural (seismic) -, 36, 454, 460, 461, 



481, 482, 581-584, 586-596, 598, 600- 



602, 604, 605, 607, 609, 615, 616, 



617, 911-913, 915, 918, 920 

 of antenna, 814, 815 

 radio -, 619, 809, 811, 812, 814-818 



