Category: Science - Physics
FORMERLY CONNECTED WITH THE OBSERVATORY OF HARVARD COLLEGE; FELLOW OF THE AMERICAN ACADEMY OF ARTS AND SCIENCES, AND MEMBER OF THE SELENO-GRAPHICAL SOCIETY OF GREAT BRITAIN; IN CHARGE OF A GOVERNMENT EXPEDITION TO OBSERVE THE TOTAL SOLAR ECLIPSE OF 1878.
FORMERLY CONNECTED WITH THE OBSERVATORY OF HARVARD COLLEGE; FELLOW OF THE AMERICAN ACADEMY OF ARTS AND SCIENCES, AND MEMBER OF THE SELENO-GRAPHICAL SOCIETY OF GREAT BRITAIN; IN...
2. Part 2The faculæ are very unstable, and are constantly changing: those of the small types sometimes form and vanish in a few minutes. When an area of disturbance of the solar surface...
3. Part 3Besides the ordinary Sun-spots already described, others are at times observed on the surface of the Sun, which show some of the same characteristics, but never attain so large...
4. Part 4The corona appears under different forms, and has never been observed twice alike. Its dimensions are also subject to considerable variations. Sometimes it appears regular and v...
5. Part 5In our northern latitudes may be seen, on every clear winter and spring evening, a column of faint, whitish, nebulous light, rising obliquely above the western horizon. A simila...
6. Part 6One of the most striking and common features of the mountainous districts of the Moon, is the circular, ring-like disposition of their elevated parts, which form numerous crater...
7. Part 7In some cases the phase of totality lasts longer than it should, according to calculation. This can be attributed to the fact that the Earth is enveloped in a dense atmosphere,...
8. Part 8On account of the inclination of the axis of rotation of this planet to the ecliptic, it is rare that both of these spots are visible on the disk at the same time; and when this...
9. Part 9In periods of calm, very few changes are noticeable in the markings of the planet, except, perhaps, some slight modifications of form in the cloudy, equatorial belt which, in ge...
10. Part 10From observations of markings seen on the surface of Saturn, and from the study of their apparent displacements on the disk, William Herschel found that the planet rotated upon...
11. Part 11Although the system of rings is very nearly concentric with the globe of Saturn, yet the coincidence is not considered as mathematically exact. It seems to have been satisfactor...
12. Part 12The large comets, such as can be seen with the naked eye, always show the following characteristics, on examination with the telescope. A condensation of light resembling a diff...
13. Part 13That the mass of comets is small, is proved by the fact that they have sometimes passed near the planets without disturbing them in any sensible manner. Lexell's comet, which in...
14. Part 14The shooting-stars were formerly considered as atmospheric meteors, caused by the combustion of inflammable gases generated at the surface of the Earth, and transported to the h...
15. Part 15Continuing its course below our horizon, the Milky-way enters Ara and Norma, and then, passing partly through Circinus, Centaurus and Musca, it reaches the Southern Cross, after...
16. Part 16The star-cluster in the constellation Hercules, designated as No. 4,230 in Sir J. Herschel's catalogue, and which is represented on Plate XIV., is one of the brightest and most...
17. Part 17The grandest and most remarkable of the annular nebulæ is found in the constellation Lyra, about midway between the two stars _β_ and _γ_. It is slightly elliptical in form, and...
18. Part 18The _method of the observation_ requires a word of explanation. Save on the rare occasions of a total solar eclipse, no direct telescopic view of the solar prominences or flames...
19. Part 19The course of the portion of the Galaxy represented in Plate XIII. is as follows: From Cassiopeia's chair, three bright stars of which appear at the upper edge of the Plate, the...