Popular Physical Astronomy; Or, an Exposition of Remarkable Celestial Phenomena
This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1858 edition. Excerpt: ...part in atmospheric phenomena. Like all light bodies, the air which surrounds us is very sensitive to electrical attraction and repulsion, and the pressure of our atmosphere must be somewhat augmented by the high state pf electricity in its upper stratum. To this elevated region an excess of the electrical fluid is confined, in consequence of the imperfect conducting power of the air near the ground, until the insulation is broken by the condensation of vapor, and the fall of rain. As the presence of moisture affords a passage for the escape of electricity from the higher atmosphere, the air is repelled from the earth, and forms an ascending current. During the ascent it is cooled by expansion, and its watery vapor condenses, so that the electrical discharge is continually repeated as the partial vacuum is filled by the influx of air from surrounding localities. This electrical convection, as it is called, Dr. Hare regards as the great motive power of the air in all hurricanes. In the present case, we can only regard heat and electricity as the two chief agencies concerned in atmospheric movements in the manner in which Espy and Hare have pointed out, but it would be difficult to determine the relative part which must be assigned to their motive powers in the disturbance of our aerial ocean. From the great violence of hurricanes in our warm climates, we may reasonably conclude that they would acquire an intolerable fury, if our globe occupied the orbit of Venus; while, on the contrary, our atmosphere would be reduced to a state of almost entire stagnation, if we were removed to the region of the asteroids. It must be recollected, however, that the movements in the great ocean of air would become violent or feeble, as its depth was...
- 189 x 246 x 3mm | 104g
- 01 Apr 2013
- Miami Fl, United States
- black & white illustrations