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acid Amphicyon angle antimonious appears atmosphere boiling point bolometer caesium fluoride calculated Carices character coal compression condenser considerable contains copper corresponding Creodonts Creosaurus crystals curve cusp cycads Cynodictis density described developed diameter dioecious distance divided circle electric Eocene epidote equations figure fluoride formation formula gases genus Geological Survey give given glaucophane heat hydrogen increase iron laccolith length less limestone located lower material measured meridian metal method mineral molar monoecious observed obtained oxide oxygen plate portion posterior premolar present pressure primary stresses probably protractor quartz rays region rock sandstone scale schist seen shales shonkinite solution species specimens spectrum sporangia stereographic projection stresses and strains structure superior molar surface synangia synangium temperature theory thickness tion transverse tube twist Uintacyon upper vibrations volume Vulpavus wave-length wire
Page 334 - The custody, maintenance, and development of the national standards of measurement, and the provision of means and methods for making measurements consistent with those standards, including the comparison of standards used in scientific investigations, engineering, manufacturing, commerce, and educational institutions with the standards adopted or recognized by the Government.
Page 334 - That the functions of the bureau shall consist in the custody of the standards; the comparison of the standards used in scientific investigations, engineering, manufacturing, commerce, and educational institutions with the standards adopted or recognized by the Government; the construction, when necessary, of standards, their multiples and subdivisions; the testing and calibration of standard measuring apparatus; the solution of problems which arise in connection with standards; the determination...
Page 155 - ... the question of the aurora and the nature of the upper air. On passing electric discharges through the tubes containing the most volatile of the atmospheric gases, they glow with a bright orange light, which is especially marked at the negative pole. The spectroscope shows that this light consists, in the visible part of the spectrum, chiefly of a succession of strong rays in the red, orange, and yellow, attributed to hydrogen, helium, and neon. Besides these, a vast number of rays, generally...
Page 155 - This shows conclusively that hydrogen in sensible proportion exists in the earth's atmosphere, and if the earth cannot retain hydrogen or originate it, then there must be a continued accession of hydrogen to the atmosphere (from interplanetary space), and we can hardly resist the conclusion that a similar transfer of other gases also must take place. The tubes containing the residue of atmospheric gases uncondensed at the temperature of liquid hydrogen we have examined spectroscppically.
Page 155 - Runge and Paschen, and some of these lines were used as lines of reference. In general, the iron spark spectrum was the standard of reference. The tubes when first examined showed the lines of the first spectrum of hydrogen vividly, and the earlier photographs of the spectrum of the negative pole contained not only the violet lines of hydrogen, but also the ultra-violet series as far up as \ 337.
Page 155 - Leyden jar in the circuit, while it more or less completely obliterates the second spectrum of hydrogen, also has a similar effect on the greater part of these other rays of, as yet, unknown origin. The violet and ultra-violet part of the spectrum seems to rival in strength that of the red and yellow rays, if we may judge of it by the intensity of its impressions on photographic plates.
Page 170 - Contributions to the Tertiary fauna of Florida, with especial reference to the silex beds of Tampa and the Pliocene beds of the Caloosahatchie River, including a complete revision of the generic groups treated of and their American Tertiary species.
Page 156 - In the spectrum of this gas the rays of helium are dominant, decidedly stronger than those of neon, although the latter are very bright. In the spectrum of the residue of atmospheric air, the proportion of helium to neon seems reversed, for in this the yellow neon line is as much more brilliant than the yellow helium line as the latter is the more brilliant in the spectrum of Bath gas. All the prominent lines in the spectrum of the volatile residue of Bath gas were also in that of the residue of...
Page 157 - This was done, and the wave-length deduced from measuring the photograph was 3727-4. This is too large by an amount which considerably exceeds the probable errors of observation, and we are forced to conclude that the nebular material is either absent from our tubes, or does not show itself under the treatment to which it has been subjected. Although the residual gases of...
Page 157 - This is too large by an amount which considerably exceeds the probable errors of observation, and we are forced to conclude that the nebular material is either absent from our tubes, or does not show itself under the treatment to which it has been subjected. Although the residual gases of the atmosphere, uncondensed at the temperature of liquid hydrogen, do not show the nebular lines, we found that another tube gave a ray very close indeed to the principal green nebular ray. This tube had been filled...