THE AMERICAN JOURNAL OF SCIENCE AND ARTS. [SECOND SERIES.] ART. XXXI.-Observations on the Zodiacal Light; with an inquiry into its Nature and Constitution, and its Relations to the Solar System; by DENISON OLMSTED, Professor of Natural Philosophy and Astronomy, in Yale College. Read before the American Association for the Advancement of Science, at the Annual Meeting at Albany, August, 1851. I SUBMIT to the Association a series of observations on the Zodiacal Light, made by me at Yale College from 1833 to 1839, upon the basis of which I propose to offer a new description of this mysterious phenomenon, and a brief inquiry into its nature and constitution, and its relations to the solar system. Particularly, I propose to inquire whether or not it is the origin of the meteoric showers of November and August. Various circumstances conspire to interrupt the continuity of a series of observations on the zodiacal light; among which are the following: 1. The comparatively few nights in the year when, in our climate, the sky is cloudless, and the atmosphere sufficiently clear to afford good observations on a light so feeble and diffuse. 2. The low angle which the zodiacal light makes with the horizon for the greater part of the year while it is visible. 3. The presence of the moon, which entirely effaces it; and, occasionally, for long periods, the presence of Venus or Jupiter, and sometimes of both planets. The light of Venus, especially, is often so bright, and the planet is so situated in the midst of the zodiacal light, as greatly to interfere with observations. Hence, a SECOND SERIES, Vol. XII, No. 36.-Nov., 1851. 40 THE AMERICAN JOURNAL OF SCIENCE AND ARTS. [SECOND SERIES.] ART. XXXI.-Observations on the Zodiacal Light; with an inquiry into its Nature and Constitution, and its Relations to the Solar System; by DENISON OLMSTED, Professor of Natural Philosophy and Astronomy, in Yale College. Read before the American Association for the Advancement of Science, at the Annual Meeting at Albany, August, 1851. I SUBMIT to the Association a series of observations on the Zodiacal Light, made by me at Yale College from 1833 to 1839, upon the basis of which I propose to offer a new description of this mysterious phenomenon, and a brief inquiry into its nature and constitution, and its relations to the solar system. Particularly, I propose to inquire whether or not it is the origin of the meteoric showers of November and August. Various circumstances conspire to interrupt the continuity of a series of observations on the zodiacal light; among which are the following: 1. The comparatively few nights in the year when, in our climate, the sky is cloudless, and the atmosphere sufficiently clear to afford good observations on a light so feeble and diffuse. 2. The low angle which the zodiacal light makes with the horizon for the greater part of the year while it is visible. 3. The presence of the moon, which entirely effaces it; and, occasionally, for long periods, the presence of Venus or Jupiter, and sometimes of both planets. The light of Venus, especially, is often so bright, and the planet is so situated in the midst of the zodiacal light, as greatly to interfere with observations. Hence, a SECOND SERIES, Vol. XII, No. 36.-Nov., 1851. 40 |