SUBJECT INDEX 



999 



Underground : 



- measurements, 14, 19, 41, 54, 242-244, 



291, 292, 404-407, 411, 413, 739, 

 811, 816, 817, 863, 884, 928-933, 

 959-962 



- openings, 14, 36, 242-244, 292 

 -workings, 14, 36, 62, 405, 815, 845, 



855, 860, 863, 928-930, 933, 958-962 

 Underwater: 



- gravimeter, 109 



- pendulum apparatus, 101, 103, 109, 



110 



- resistivity surveys, 738 



- sound receiver, 947-956 



- sound transmitter, 945-956 

 Undograph, 937 

 Uraninite, density of, 77 

 Uranium, 35, 51, 52, 870, 872-875, 880 



V 



Vacuum, free fall in, 123 

 Vagabondary currents, 63 

 Valentinite, density of, 77 

 Vanadinite, density of, 77 

 Vanadium, 51, 52 

 Variation : 



annual temperature -, 860-862 



artificial magnetic -, 372 



diurnal magnetic -, 41, 42, 331, 332, 

 366-369, 371 



diurnal temperature -, 860 



- of gravity field, 162-167 

 -recording, 18, 41, 42, 63, 164, 331, 



332, 366-372, 755 



secular -, 370, 371 



stratigraphic (shallow) (see Near- 

 surface interference) 

 Variometer: 



gravity - (see Torsion balance) 



magnetic - (see Magnetometer and 

 Observatory) 

 Vector potential (see Potential) 

 Vectors, anomalous, 378-380, 405-407, 



411, 413, 417, 418 

 Vehicles, measurements in, 41, 42 

 Veins, 29, 50, 52, 150, 162, 259, 260, 264, 

 287, 385, 395, 396, 413, 624, 625, 

 729, 740, 749-751, 755, 774, 803, 

 816, 883, 884 

 Velocity : 



apparent - (see Seismic wave velocity, 

 apparent) 



average - (see Seismic wave velocity, 

 average) 



bar - 461, 463, 482 



differential - (see Seismic wave ve- 

 locity, differential) 



light - (see Light velocity) 



phase - (see Phase speed) 



seismic - (see Seismic wave velocity) 



Sound - (see Sound velocity) 



vertical - (see Seismic wave velocity, 

 vertical) 



Vertical : 



- balance (see Magnetometer, Schmidt 



vertical) 



- component (see Vertical component) 

 deflections of -, 70, 167-170 



- electrical drilling (see Resistivity 



sounding) 



- gradient of gravity, 70, 136, 169, 



190-192 



- gradiometer (see Gradiometer) 

 -intensity. 16-18, 295, 302, 320, 321, 



323, 326-328, 335-337, 339-341, 

 344, 345, 348, 378-402, 405-412, 

 414-417, 420, 423, 425-429, 431, 

 432, 434-436 



- loops (see Loops) 



- m^netometer (see Magnetometer, 



Schmidt vertical) 



- ray interpretation, 533-536, 549 



- shooting, 23, 557, 560 



- seismograph (see Seismograph) 



- variation of seismic and sound 



velocity, 23, 474, 476, 533, 540-646, 

 560, 565, 935, 936, 943, 944 



- velocity (see Seismic wave velocity, 



vertical) 



- velocity gradient (see Vertical varia- 



tion of seismic and sound velocity) 

 Vertical component: 



- of gravity, 88, 124, 164, 168 



- of ground and building vibration, 20, 



551, 918 



- of electrical field (see Electrical field) 



- of electromagnetic field (see Electro- 



magnetic field) 



- of magnetic field (see Vertical in- 



tensity) 

 Vibration: 

 acoustic - (see Acoustic waves) 

 blasting -, 36, 911, 913, 931 

 bridge -, 912, 915, 917 

 building -, 6, 36, 911, 912, 918, 919 

 dam -, 912 



- damage, 9, 910, 911, 913 



- detector, 866, 867, 916 

 earthquake -, 36, 912, 918 

 flexural -, 912, 919 



forced -, 36, 62, 461, 481, 586-591, 911, 



912 917-919 

 free -, 62, 86, 97, 100, 356, 449, 461, 



582-586, 598, 615, 616, 911, 912-914 

 frequency of - (see Frequency) 

 ground -, 912-914, 919-925 

 industrial -, 36, 910 

 pipe -, 866, 867, 982 



- recording, 36, 58, 912-928 



- of roads, 6 



- of rock specimens: 

 longitudinal vibrations, 462-463 

 torsional vibrations, 461-4^3 



shear -, 912, 919 



- testing, 9, 36, 41, 911 

 torsional -, 912 



