Astronomy concerns itself with the whole of the visible universe, of which our earth forms but a relatively insignificant part; while Geology deals with that earth regarded as an individual. Astronomy is the oldest of the sciences, while Geology is one of the newest. But the two sciences have this in common, that to both are granted a magnificence of outlook, and an immensity of grasp denied to all the rest.
Proceedings of the Geological Survey of London. "Gaither's Dictionary of Scientific Quotations" by Carl C. Gaither, p. 873, 2012.