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 was out.— The Bookseller said he had not read it but had heard it was a very remarkable book!!!" In December 1859 the botanist Asa Gray negotiated with a Boston publisher for publication of an authorised American version, however, he learnt that two New York publishing firms were already planning to exploit the absence of international copyright to print "Origin". Darwin wrote in January, "I never dreamed of my Book being so successful with general readers: I believe I should have laughed at the idea of sending the sheets to America." and asked Gray to keep any profits. Gray managed