[Intimate Nature of the Forces] [24]

[Sunlight and sun-heat][The great law of conservation][How the spheres are constructed][The great earth-core and its functions][The grand magnetic circuit.]

[CHAPTER IV.]

[Sunlight, its Source and Nature] [29]

[Its limits][The solar cone][The sun not incandescent][New hypothesis][No borrowed light][The sun dependent][Light as a substance][Velocity of Light].

[CHAPTER V.]

[Sun-Heat, its Source and Limits] [35]

[Tendencies to unsettle in science][Present theories][True source][Earth's part in the process][Sun's part][New philosophy][Old phenomena and new interpretations][Auroræ][Well understood processes in confirmation][The ordinary battery][The Great Sun Battery][Heat without combustion][Inter-currents][Solution of the problem].

[CHAPTER VI.]