804 



SMITHSONIAN PHYSICAL TABLES 



Gauss, 18 



Gaussian system of units, 15 

 Gem lamps, color temperature, 104 

 General physical constants, 46 

 discussion of, 46 



tables according to Bearden and Watts, 54 

 Birge, 47 



Du Mond and Cohen, 51 

 General precession, 738 



Geographical data (see also under Astron- 

 omy and Oceanography), 728, 772 

 Geologic strata, ages, 741 

 Geomagnetism, 468 

 coordinates, 468 



north magnetic pole, 470 

 position on earth, 493 

 south magnetic pole, 471 

 earth, as a dipole, 469 



geomagnetic coordinates of position, 493 

 magnetic — 

 axis, 502 



characteristics, 502 

 data, 502 

 dip in U.S.A., 471 



disinclination, hourly departure from 

 normal, 477, 478 

 isogonic, 472 



secular change in U.S.A., 479 

 field, elements of, 468 

 horizontal intensity (isodynamic), 



474 

 inclination (isoclinic), 473 

 intensity, horizontal, U.S.A., 478 

 total, U.S.A., 480 

 vertical, U.S.A., 479, 480 

 moment, 470 

 pole (earth), 470, 471 

 potential, Gauss coefficients, 470 

 spherical harmonic coefficients, 470 

 surveys, 469 



United States, dip or inclination, 471 

 horizontal magnetic intensity, 478 

 secular change of dip, 471 

 secular change of horizontal in- 

 tensity, 479 

 secular change of magnetic declina- 

 tion, 478 

 secular change of total intensity, 



480 

 secular change of vertical intensity, 



480 

 total magnetic intensity, 480 

 vertical magnetic intensity, 479 

 values of magnetic elements at ob- 

 servatories, 481 

 variations, 469 

 world isoclinic lines, 473 

 world isodynamic lines, 474 

 horizontal intensity, 474 

 total intensity, 476 

 vertical intensity, 475 

 world isogonic lines, 472 

 sun, magnetic data, 502 

 Geometrical units. 4 



definitions, 3-4 

 Geophysical data, 739-741 

 Giga, 5 



Gilbert, 18, 22 



Glass, compressibility, 289 



emissivity at low temperatures, 100 

 optical, 509 



characteristics, American made, 509 

 foreign made, 514 



National Bureau of Standards, 510 

 coefficient of expansion, 529 

 index of refraction, 509 



change with temperature, 513 

 nu values, 509 



temperature, 513 

 physical properties, special glasses, 534 

 specific gravity, 529 

 stain class, 529 



physical properties, 529 

 transmission, 512, 514, 535 

 red pyrometer, effective wavelength, 537 



transmission, 537 

 reflection, Fresnel formula, 549 

 resistivity, 396 



special, physical properties, 534 

 stain, 529 



expansion, 529 

 specific gravity, 529 

 vessels, volume, 68 

 viscosity, 330 

 Glycerol-water, 321 

 Gram, 5 



Gram-centimeter, 5, 21 

 Gram-mass, 21 

 Gram-molecule, 5 

 Gravitation, 714 



acceleration of gravity at different lati- 

 tudes, 714 

 free-air correction for altitude, 714 

 log, 714 



United States, 716 

 various world stations, 715 

 anomalous gravity, some places of, 718 

 constant, 5, 47 



length of seconds pendulum, 717 

 Gravity, specific, 5 

 unit, 5, 729 

 API scale, 290 

 specific, Baume scale, 289 

 Graybody, 8 



Gunter's chain, length, 62 

 Gyration, radius of, 27 



h. 653 



h or k, 653 



H-ray, 653 



Hall constant, 507 



variation with temperature, 508 

 Hall effect, 451 

 Hardness, 187, 227 

 Brinell, 187 



relative, of elements, 228 

 of plastics, 239 

 of various materials, 228 

 Poisson's ratio, 227 

 scale of, 227 

 Shore scleroscope, 188 

 Hearing (see also Sound), differential sensi- 

 tivity, 314 



