On the Origin of Species more recent study by science historian John van Wyhe has determined that the idea that Darwin delayed publication only dates back to the 1940s, and Darwin's contemporaries thought the time he took was reasonable. Darwin always finished one book before starting another. While he was researching, he told many people about his interest in transmutation without causing outrage. He firmly intended to publish, but it was not until September 1854 that he could work on it full-time. His 1846 estimate that writing his "big book" would take five years proved optimistic. An 1855 paper on the "introduction" of species, written
On the Origin of Species be impossible." He asked Hooker how many pages would be available, but "If the Referees were to reject it as not strictly scientific I would, perhaps publish it as pamphet." He began his "abstract of Species book" on 20 July 1858, while on holiday at Sandown, and wrote parts of it from memory, while sending the manuscripts to his friends for checking. By early October, he began to "expect my abstract will run into a small volume, which will have to be published separately." Over the same period, he continued to collect information and write large fully detailed sections of