SUBJECT INDEX' 



Aaregranite, susceptibility of, 313 

 ABC system, 548, 549, 572, 576 

 Abdank-Abakanovicz integraph, 249 

 Abnormal polarization {see Polarization) 

 Abrasives, 550 

 Absorption and attenuation: 



- coefficients {see Coefficients) 



- of electric currents and radiation, 



627, 652, 685, 686, 809, 811, 812, 813 



- of radioactive radiation, 870-873, 881 



- of seismic energy, 480, 492, 924 



- of sound waves {see Sound, absorp- 



tion of -) 

 A.C. {see Alternating current) 

 Acceleration: 



- in fan shooting, 500-501 



- of gravity {see also Gravitational 



field and Gravity), 88, 89, 454 



- of ground motion, 447-449, 477, 586, 



587, 590, 593, 920 



- vectors, 500, 501 

 Accelerometer, 586, 587, 590, 593, 613 

 Acetylenes, 889 



Acidity of soils, 647, 680 

 Acoustic: 



- communication, 937-939, 945, 949, 960 



- compensators, 938, 939, 942, 948, 949, 



951 952 961 



- direction-finding, 938, 941, 942, 951, 



960-962 



- echo-sounding {see Echo-sounding) 



- frequencies in acoustic methods, 866, 



937, 940, 941, 945, 946, 949, 952, 

 953, 955, 958 



- intensity, 477-481 



- methods, 9, 36, 41, 58, 934-963 



- noise-detection, 941, 942, 951, 960-962 



- opacity, 480 



- position-finding, 937, 939, 940, 949, 



960 



- ranging {see Sound-ranging and 



RAR system) 



- receivers {see Sound receivers) 



- resistance, specific, 477-479, 947, 949 



- transmission measurements, 962 



- transmitters {see Sound transmit- 



ters) 



Acoustic {cont'd): 



- transparency, 480 



- triangulation, 940, 942, 949, 950, 960 



- waves {see also Sound, Seismic 



waves), 435-436, 943-945, 956-958 



- well measurements, 35, 866, 867, 942, 



943 

 Actinium, 873 

 Actinon, 873 



Activity, electrochemical {see Polariza- 

 tion, spontaneous) 

 Agitator {see Vibrator) 

 Air: 

 radioactivity of -, 874 

 sound velocitv in -, 468, 867, 935, 941, 

 943 

 ylirplane : 

 detection of -, 9, 41, 64, 941, 942 

 measurements in -, 7, 19, 41, 42, 363, 

 365, 407, 408, 813 

 Air-pr£3sure correction, 10, 118, 133 

 Albite, density of, 80 

 Alluvium: 

 density of -, 82 



longitudinal wave velocity of -, 469 

 Rayleigh wave velocity of -, 473 

 resistivity of -, 664 

 Alpha rays and alpha radiation, 863, 864, 



871-873, 882, 884, 885 

 Alternating current in electrical pros- 

 pecting, 25, 619, 624, 630, 642-649, 

 681, 685-696, 701, 752, 760, 761, 

 763-765, 774 

 Alternator {see Generator) 

 Altimeter, 64, 813, 942 

 American mining compass, 346 

 Ames gauges, 454 

 Ammunition, 63, 297, 435, 436, 624, 627, 



706 

 Amphiboles : 

 density of -, 80 

 elastic moduli of -, 467 

 Amphibolites: 

 density of -, 81 

 susceptibility of -, 312 

 Amplifier : 



- in electrical prospecting, 27, 29, 30, 



695, 696, 701, 758-761, 765, 774, 775, 

 778-782, 784^786, 820, 821, 823, 824 



^ Geographical names will be found in the Name and Place Indes. 



965 



