Miscellaneous Scientific Papers of the Allegheny Observatory of the University of Pittsburgh. New Series, Volumes 1-2New Era Printing Company, 1910 Consists of papers contributed to various astronomical journals and societies, annual reports of the Director, and special circulars and announcements issued by the Observatory |
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aberration absorption accuracy Allegheny Observatory already angle angular aperture Astronomical Astrophysical Journal axis Brashear building Cepheid variables clock coefficient collimator complete concave grating considerable construction cos² curvature definition determine diffraction Director displacement effect equation error F. L. O. WADSWORTH field flint focal length focal plane focus FRANK SCHLESINGER given glass heliometer increase instrument investigation Keeler lens Lick Observatory light lines maximum measurement ment meridian circle method mirror mounting objective spectroscope observations obtained optical paper Phil photographic photospheric position prism train Prof Professor Langley radiation ratio rays reflecting telescope refraction resolving power resolving-power S. P. Langley scientific slit spectral image spectrograph spectroscopic binaries spectrum spherical stars surface Table telescope temperature tenth-meters tion UNIV values variation visual binaries Volume wave-front wave-length width William Thaw Yerkes Observatory Δλ
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Page 2 - ... to say of the gloomy prospect. If I remember aright, he first told them that, incredible as it might seem, there was not only a time in the world's youth when the mushroom itself was young, but that the sun in those early ages was in the eastern, not in the western, sky. Since then, he explained, the eyes of scientific ephemera had followed it, and established by induction from vast experience the great
Page 2 - ... decline, from that which saw it rise. Imagine the sun about to set, and the whole nation of mites gathered under the shadow of some mushroom (to them ancient as the sun itself) to hear what their wisest philosopher has to say of the gloomy prospect.
Page 9 - JOURNAL, 14, 349, December 1901.) Above this lower zone and to a height of half a degree, "comparisons with a sky spectrogram secured with the same instrument show that the coronal and sky spectra are sensibly identical in the blue and violet regions" (p. 354). Polariscopic observations also show that the light from the outer corona agrees with that of the sky in being polarized, and consequently we may assume that the coronal envelope, like the Earth's atmosphere, contains finely divided matter...
Page 14 - Publications of Learned Societies and Periodicals in the Library of the Smithsonian Institution.
Page 3 - On the Conditions of Maximum Efficiency in the Use of the Spectrograph," ASTROPHYSICAL JOURNAL, 3, 335, May 1896.
Page 10 - The corona is effectively cooler than the bolometer, and appears, therefore, neither to reflect much light from the Sun nor chiefly by virtue of a high temperature to give light of its own, but seems rather to be giving light in a manner not associated with a high temperature, or at least with the preponderance of infra-red rays usual in the spectra of hot bodies.
Page 3 - ... of Naval Research. There is no assured source for meeting the Board's future administrative expenses, although it is being called upon increasingly to furnish advice and assistance on both national and international problems concerned with science in the Pacific. Committee on Undersea Warfare.- — During the past year two new members have been added to the committee: Dr. Lyman Spitzer, Jr.. of Princeton University, and Dr. Harvey Brooks of the General Electric Co. Mr. TE Shea has resigned from...
Page 1 - ... of an inch nearer the mirror than those from its central parts. If, now, the converse experiment be tried, and a mirror of the same size and focal length, which can converge parallel rays falling on all its parts to one focus, be examined at the center of curvature, it gives there an amount of longitudinal aberration 10-100 of an inch, equal to twice the preceding.
Page 13 - Instruments. (2) A Simple Method of Determining the Eccentricity of a Graduated Circle with One Vernir.