New Theories in Astronomy

CHAPTER I.. The Bases of Modern Astronomy. Their Late Formation 18

The bases of modern astronomy. Their late formation 18 Instruments and measures used by ancient astronomers 19 Weights and measures sought out by modern astronomers 20 Means employed to discover the density of the earth. Measuring by means of plummets not sufficiently exact 20 Measurements with torsion and chemical balances more accurate 21 Sir George B. Airy's theory, and experiments at the Harton colliery 22 Results of experiments not reliable. Theory contrary to the Law of Attraction 23 Proof by arithmetical calculation of its error 24 Difficulties in comparing beats of pendulums at top and bottom of a mine 26 The theory upheld by text-books without proper examination 27 Of a particle of matter within the shell of a hollow sphere. Not exempt from the law of Attraction 28 A particle so situated confronted with the law of the inverse square ofdistance from an attracting body. Remarks thereon 29 It is not true that the attraction of a spherical shell is "zero" for a particle of matter within it 31

CHAPTER II.. The Moon Cannot Have Even an Imaginary Rotation on Its Axis,

The moon cannot have even an imaginary rotation on its axis, but is generally believed to have. Quotations to prove this 33 Proofs that there can be no rotation. The most confused assertion that there is rotation shown to be without foundations 35 A gin horse does not rotate on its axis in its revolution 37 A gin horse, or a substitute, driven instead of being a driver 38 Results of the wooden horse being driven by the mill 38 The same results produced by the revolution of the moon. Centrifugal force sufficient to drive air and water away from our side of the moon 39 That force not sufficient to drive them away from its other side 40 No one seems ever to have thought of centrifugal force in connection with air and water on the moon 41 Near approach made by Hansen to this notion 41 Far-fetched reasons given for the non-appearance of air and water 42 The moon must have both on the far-off hemisphere 44 Proofs of this deduced from its appearance at change 44 Where the evidences of this may be seen if looked for at the right place. The centrifugal force shown to be insufficient to drive off even air, and less water, altogether from the moon 45 The moon must have rotated on its axis at one period of its existence 47 The want of polar compression no proof to the contrary 48 Want of proper study gives rise to extravagant conceptions, jumping at conclusions, and formation of "curious theories" 48

CHAPTER III.. Remarks on Some of the Principal Cosmogonies. Ancient Notions 49

Remarks on some of the principal cosmogonies. Ancient notions 49 The Nebular hypothesis of Laplace. Early opinions on it. Received into favour. Again condemned as erroneous 50 Defects attributed to it as fatal. New cosmogonies advanced 51 Dr. Croll's collision, or impact, theory discussed 53 Dr. Braun's cosmogony examined 59 M. Faye's "Origine du Monde" defined 61 Shown to be without proper foundation, confused, and in some parts contradictory 65 Reference to other hypotheses not noticed. All more or less only variations on the nebular hypothesis 70 Necessity for more particular examination into it 71

CHAPTER IV.. Preliminaries to Analysis of the Nebular Hypothesis 72

Preliminaries to analysis of the Nebular hypothesis 72 Definition of the hypothesis 73 Elements of solar system. Tables of dimensions and masses 75 Explanation of tables and density of Saturn 78 Volume, density and mass of Saturn's rings, general remarks about them, and satellites to be made from them 79 Future of Saturn's rings 79 Notions about Saturn's satellites and their masses 80 Nature of rings seemingly not well understood 81 Masses given to the satellites of Uranus and Neptune. Explanations of 81 Volumes of the members of the solar system at density of water 82

CHAPTER V.. Analysis of the Nebular Hypothesis. Separation From the Nebula

Analysis of the Nebular Hypothesis. Separation from the nebula of the rings for the separate planets, etc. 83 Excessive heat attributed to the nebula erroneous and impossible 84 Centigrade thermometer to be used for temperatures 85 Temperature of the nebula not far from absolute zero 86 Erroneous ideas about glowing gases produced by collisions of their atoms, or particles of cosmic matter in the form of vapours 86 Separation of ring for Neptune. It could not have been thrown off in one mass, but in a sheet of cosmic matter 87 Thickness and dimensions of the ring 88 Uranian ring abandoned, and its dimensions 89 Saturnian ring do. do. 90 Jovian ring do. do. 91 Asteroidal ring do. do. 93 Martian ring do. do. 94 Earth ring do. do. 95 Venus ring do. do. 96 Mercurian ring do. do. 97 Residual mass. Condensation of Solar Nebula to various diameters, and relative temperatures and densities 98 Unaccountable confusion in the mode of counting absolute temperature examined and explained. Negative 274 degrees of heat only equal 2 degrees of absolute temperature 100 The Centigrade thermometric scale no better than any other, and cannot be made decimal 103 The sun's account current with the Nebula drawn up and represented by Table III. 104

CHAPTER VI.. Analysis Continued. Excessive Heat of Nebula Involved

Analysis continued. Excessive heat of nebula involved condensation only at the surface. Proof that this was Laplace's idea 108 Noteworthy that some astronomers still believe in excessive heat 109 Interdependence of temperature and pressure in gases and vapours. Collisions of atoms the source of heat 110 Conditions on which a nebula can be incandescent. Sir Robert Ball 110 No proper explanation yet given of incandescent or glowing gas 112 How matter was thrown off, or abandoned by the Jovian nebula 115 Division into rings of matter thrown off determined during contraction 116 How direct rotary motion was determined by friction and collisions of particles 117 Saturn's rings going through the same process. Left to show process 118 Form gradually assumed by nebulæ. Cause of Saturn's square-shouldered appearance 120 A lens-shaped nebula could not be formed by surface condensation 120 Retrograde rotary motion of Neptune and Uranus, and revolution of their satellites recognised by Laplace as possible 121 Satellites of Mars. Rapid revolution of inner one may be accounted for 123 Laplace's proportion of 4000 millions not reduced but enormously increased by discoveries of this century 124

CHAPTER VII.. Analysis Continued. No Contingent of Heat Could Be Imparted

Analysis continued. No contingent of heat could be imparted to any planet by the parent nebula 126 Only one degree of heat added to the nebula from the beginning till it had contracted to the density of 1/274th of an atmosphere 127 Increase in temperature from 0° to possible average of 274° when condensed to 4,150,000 miles in diameter 127 Time when the sun could begin to act as sustainer of life and light anywhere. Temperature of space 128 The ether devised as carrier of light, heat, etc. What effect it might have on the nebula 129 First measure of its density, as far as we know 130 The estimate too high. May be many times less 133 Return to the solar nebula at 63,232,000 miles in diameter 134 Plausible reason for the position of Neptune not conforming to Bode's Law. The ring being very wide had separated into two rings 134 Bode's law reversed. Ideas suggested by it 135 Rates of acceleration of revolution from one planet to another 137 Little possibility of there being a planet in the position assigned to Vulcan 138 Densities of planets compared. Seem to point to differences in the mass of matter abandoned by the nebula at different periods 138 Giving rise to the continuous sheet of matter separating into different masses. Probably the rings had to arrive at a certain stage of density before contracting circumferentially 139 Possible average temperature of the sun at the present day. Central heat probably very much greater 140 Churning of matter going on in the interior of the sun, caused by unequal rotation between the equator and the poles 140

CHAPTER VIII.. Inquiry Into the Interior Construction of the Earth.

Inquiry into the Interior Construction of the Earth. What is really known of the exterior or surface 142 What is known of the interior 143 Little to be learned from Geology, which reaches very few miles down 144 Various notions of the interior 145 What is learnt from earthquake and volcanoes. Igno-aqueous fusion, liquid magma. 146 Generally believed that the earth consists of solid matter to the centre. Mean density. Surface density 147 More detailed estimate of densities near the surface 148 Causes of increased surface density after the crust was formed 148 Calculations of densities for 9 miles deep, and from there to the centre forming Table IV. 150 Reflections on the results of the calculations 151 Notion that the centre is composed of the heaviest metals. "Sorting-out" theory absurd 151 Considerations as to how solid matter got to the centre 152 Gravitation might carry it there, but attraction could not 153 How the earth could be made out of cosmic matter, meteorites or meteors 154

CHAPTER IX.. Inquiry Into the Interior Construction of

Inquiry into the Interior Construction of the Earth--continued 165 The earth gasiform at one period. Density including the moon may have been 1/10,000th that of air. Must have been a hollow body. Proofs given 166 Division of the mass of the earth alone into two parts 169 Division of the two masses at 817 miles from surface 171 Reasons why the earth cannot be solid to the centre 172 Gasiform matter condensing in a cone leaves apex empty 172 Proportions of the matter in a cone 173 Calculations of the densities of the outer half of the hollow shell of the earth. Remarks upon the condensation 174 Calculations of inner half of the hollow shell 175 Remarks upon position of inner surface of the shell 177 Calculations of the same 179

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