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Robert S. Ball. The Earth's Beginning
The Earth's Beginning
Table of Contents
FOREWORD
CHAPTER I. INTRODUCTION
CHAPTER II. THE PROBLEM STATED
CHAPTER III. THE FIRE-MIST
CHAPTER IV. NEBULÆ—APPARENT AND REAL
CHAPTER V. THE HEAT OF THE SUN
CHAPTER VI. HOW THE SUN’S HEAT IS MAINTAINED
CHAPTER VII. THE HISTORY OF THE SUN
CHAPTER VIII. THE EARTH’S BEGINNING
CHAPTER IX. EARTHQUAKES AND VOLCANOES
CHAPTER X. SPIRAL AND PLANETARY NEBULÆ
CHAPTER XI. THE UNERRING GUIDE
CHAPTER XII. THE EVOLUTION OF THE SOLAR SYSTEM
CHAPTER XIII. THE UNITY OF MATERIAL IN THE HEAVENS AND THE EARTH
CHAPTER XIV. THE FIRST CONCORD
CHAPTER XV. THE SECOND CONCORD
CHAPTER XVI. THE THIRD CONCORD
CHAPTER XVII. OBJECTIONS TO THE NEBULAR THEORY
CHAPTER XVIII. THE BEGINNING OF THE NEBULA
CHAPTER XIX. CONCLUDING CHAPTER
APPENDICES
I.—ON THE HEAT GIVEN OUT IN THE CONTRACTION OF THE NEBULA
§ 1. Fundamental Theorems in the Attraction of Gravitation
§ 2. On the Energy between Two Attracting Masses
§ 3. On the Energy Given Out in the Contraction of the Nebula
§ 4. Evaluation of the Sun Heat Given Out in Contraction
§ 5. On the Further Contraction of the Sun and the Heat that may thus be Given Out
§ 6. On the Present Emission of Sun Heat
§ 7. On the Daily Contraction of the Sun Necessary to Supply the Present Expenditure of Heat
II.—THE CONSERVATION OF MOMENT OF MOMENTUM
§ 8. Case where there are no forces
§ 9. A Geometrical Proposition
§ 10. Relation Between the Change of Moment of Momentum and the Force Acting on the Particle
§ 11. If Two or More Forces Act on a Point, then the Acceleration of the Moment of Momentum, due to the Resultant of these Forces, is Equal to the Algebraic Sum of the Moments of Momentum due to the Action of the Several Components
§ 12. If any Number of Particles be Moving in a Plane, and if they are not Subjected to any Forces save those which arise from their Mutual Actions, then the Algebraic Sum of their Moments of Momentum round any Point is Constant
§ 13. If a Particle of Mass m, is Moving in Space under the Action of any Force F, then the Projection of that Particle on any Fixed Plane will Move as if it were a Particle of Mass m Acted upon by that Component of F which is Parallel to the Plane
§ 14. On the Principal Plane of a System
§ 15. Collisions
§ 16. Friction and Tides
INDEX
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Robert S. Ball
Published by Good Press, 2022
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In our study of the heavens we must strive to avoid inferences so utterly fallacious as these which I have here tried to illustrate. Let it be granted that to our superficial view the sun and the moon, the stars and the constellations present features which appear to us as eternal as the bole of the oak seemed to the butterfly. But though the sun may seem to us always of the same size and always of the same lustre, it would be quite wrong to infer that the lustre and size of the sun are in truth unchanging. The sun is no more unchanging than the oak-tree is eternal. The sun and the earth, no less than the other bodies of the universe, are in process of a transformation no less astonishing than that wonderful transformation which in the course of centuries develops an acorn into the giant of the forest. We could not indeed with propriety apply to the great transformation of the sun the particular word growth; the character of the solar transformation cannot be so described. The oak-tree, of course, enlarges with its years, while the sun, on the other hand, is becoming smaller. The resemblance between the sun and the oak-tree extends no further than that a transformation is taking place in each. The rate at which each transformation is effected is but slow; the growth of the oak is too slow to be perceived in a day or two; the contraction of the sun is too slow to be appreciable within the centuries of human history.
Whatever the butterfly’s observation might have suggested with regard to the eternity of the oak, we know there was a time when that oak-tree was not, and we know that a time will come when that oak-tree will no longer be. In like manner we know there was a time when the solar system was utterly different from the solar system as we see it now; and we know that a time will come when the solar system will be utterly different from that which we see at present. The mightiest changes are most certainly in progress around us. We must not deem them non-existent, merely because they elude our scrutiny, for our senses may not be quick enough to perceive the small extent of some of these changes within our limited period of observation. The intellect in such a case confers on man a power of surveying Nature with a penetration immeasurably beyond that afforded by his organs of sense.
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