Reactions to On the Origin of Species man to be envious of a naturalist like myself, immeasurably his inferior!" Darwin's had estimated that erosion of the Weald would take 300 million years, but in the second edition of "On the Origin of Species" published on 7 January 1860 he accepted that it would be safer to allow 150 million to 200 million years. Geologists knew the earth was ancient, but had felt unable to put realistic figures on the duration of past geological changes. Darwin's book provided a new impetus to quantifying geological time. His most prominent critic, John Phillips, had investigated how temperatures increased with depth
Reactions to On the Origin of Species to showing you the varieties of those species, or of any of those phenomena that would aid one in getting at that mystery of mysteries, the origin of species, our space does not permit; but surely there ought to be a space somewhere, and, if not in the British Museum, where is it to be obtained?" Huxley's April review in the "Westminster Review" included the first mention of the term "Darwinism" in the question, "What if the orbit of Darwinism should be a little too circular?" Darwin thought it a "brilliant review." Overflowing the narrow bounds of purely scientific circles,