George Moore criticized the moral and structural power the circulating library system had on literary distribution. His response to censorship was to issue a number of polemics against circulating libraries, the most popular being "Literature at Nurse, or Circulating Morals". He confronted Mudie on why the librarian refused to sell "A Modern Lover". Mudie's response:"Your book was considered immoral. Two ladies from the country wrote to me objecting to that scene where the girl sat to the artist as a model for Venus. After that I naturally refused to circulate your book, unIess any customer said he wanted particularly to read Mr. Moore's novel." Mudie was also crucial in the success of scientific volumes – In November 1859 he bought 500 copies of the first publication of Charles Darwin's "On the Origin of Species". In fact, much of Darwin's own reading was obtained from Mudie's nonfiction collection. His five-guinea annual subscription allowed him to borrow a parcel of up to six recently published books a month.