Note 20 — Chapter XVI · EQUILIBRATION.

Until I recently consulted his “Outlines of Astronomy” on another question, I was not aware that so far back as 1833, Sir John Herschel had enunciated the doctrine that “the sun’s rays are the ultimate source of almost every motion which takes place on the surface of the earth.” He expressly includes all geologic, meteorologic, and vital actions; as also those which we produce by the combustion of coal. The late George Stephenson appears to have been wrongly credited with this last idea.