... simple and orderly manner, certain of my own theories of the Great Physical Forces. In these theories will be comprised the identity of those forces, the intimate and essential nature of sunlight, ... position at the present day. The present theories of the transmission of light and sound; of the production of winds, and sun-spots, and of the method of development and dissemination of heat, ... What is the intimate and inherent nature of those forces? Do they, or either of them, belong to the domain of the supernatural? Are they the products of some supreme force, or forces, heretofore...