The remarkable resemblance between the mode of operation and effects of these electrical induction machines and the vast rotating electrosphere of the earth must be at once apparent. The operation is precisely the same, and the results must, pari passu, be substantially similar. We need not seek for precise parallelism of structure, because these machines themselves, it has been shown, widely differ in structure among themselves. But the almost infinitely more vast terrestrial electrosphere, which cannot be less than ten thousand miles in diameter, and perhaps much more (if we may form an opinion from the relative magnitude of the field of action of the hydrogen envelope which constitutes the solar electrosphere), rotating in the attenuated vapors of space, among which vapors that of water plays a most important part, and which vapors constantly impinge with various disturbances of contact against the more and more attenuated layers of the terrestrial atmosphere, and which gradually, from within outward, less and less partakes of the earth's rotation until, finally, its rotatory movement is lost in the vast ocean of space, establishes the certainty that enormous quantities of electricity must there be disengaged, precisely as in the machines which we have described, and to learn the potential or active pressure of this electricity we have only to consider the fact that we find a rise so rapid, as we ascend through our atmosphere, that the potential increases by from twenty to forty volts for each foot. That these currents are transmitted to the sun without appreciable resistance we already know, and that they are there transformed into light and heat we can, from the previously cited experiments, see.