 By mid January 1832, early in the "Beagle" voyage, Darwin saw geology from Charles Lyell's viewpoint.When the second volume of Lyell's "Principles of Geology" was delivered to the "Beagle" that November, Darwin accepted its argument that the "struggle for existence" disproved transmutation of species.He was reminded of Malthusianism when his sisters sent him out pamphlets by Harriet Martineau.