“Combining in our survey then, the whole range of deposits from the most recent to the most ancient group, how striking a succession do they present:- so various yet so uniform-so vast yet so connected. In thus tracing back to the most remote periods in the physical history of our continents, one system of operations, as the means by which many complex formations have been successively produced, the mind becomes impressed with the singleness of nature's laws; and in this respect, at least, geology is hardly inferior in simplicity to astronomy.”
Source : Roderick Impey Murchison (1839). “The silurian system, founded on geological researches in the counties of Salop, Hereford etc”, p.574
