Page:Popular Science Monthly Volume 2.djvu/674

654 of its parts toward the centre, and the process of cooling at its (surface, the rotation must necessarily be accelerated, and consequently the centrifugal force augmented, particularly at its equatorial parts. In fact, this could not be done-without the use of illustrative diagrams. Suffice it to state, that the final result would be, the development of a system of planets, revolving in a common direction around a vast central solar mass, with subordinate systems of satellites circulating in a like direction around their primaries. These are precisely the arrangements which are found to exist in our solar system.

Assuming that the primitive solar nebula rotated on its axis, as the sun does, from west to east, the following consequences were deduced from the theory, viz.: 1. All the planets should move around the sun from west to east. 2. All the planets should rotate on their axes from west to east. 3. All the satellites should rotate on their axes from west to east. 4. All the planets should revolve about the sun in orbits nearly coincident with the plane of the solar equator. 5. All the satellites should revolve about their primaries nearly in the planes of the equators of their respective planets. 6. All the planets should revolve in orbits of small eccentricity. 7. All the satellites should revolve in orbits of small eccentricity. 8. The central mass—the sun—should rotate on his axis in less time than any of the planets revolve about him in their orbits. 9. The primary planets should revolve on their axes in less time than any of their satellites revolve around them; and 10. The central mass, left after the process of genesis was completed, should contain a much larger quantity of matter than the sum of the masses separated. All of these arrangements (with a few unimportant deviations), were shown to exist in the solar system. Recapitulating these coincidences, we obtain the following significant results, viz.:

"We thus see that there are no less than 390 independent phenomena—of which the law of gravitation gives no account—which are simple consequences of the Nebular Hypothesis. In the aggregate, they imply a very large number of facts—complex—diverse—unconnected with each other—having no mutual dependence—all accounted for by a simple supposition, and the aid of the known laws of matter and motion." It can hardly be denied that, regarded as a pure