'I daresay I shall not keep my resolution, but I will try to do it firmly, that when my book is attacked ... I will not go to the expense of time in pamphleteering. I shall work steadily on Vol. II, and afterwards, if the work succeeds, at edition 2, and I have sworn to myself that I will not go to the expense of giving time to combat in controversy. It is interminable work[57].' In order to maintain this resolve, Lyell, the moment the last sheet of the volume was corrected, set off for a four months' tour in France and Spain. While absent from England, he heard little of what was going on in the scientific world; but, on his return, Lyell was told by Murray that in the three months before the _Quarterly Review_ article appeared, 650 copies of the volume, out of the 1500 printed, had been sold, and he anticipated the disposal of many more, when the review came out. This expectation was realised and led to the issue of a second edition of the first volume, of larger size and in better type. Lyell, from the first, had seen that it would be impossible to avoid the conclusion that the principles which he was advancing with respect to the inorganic world must be equally applicable to the organic world. At first he only designed to touch lightly on this subject, in the concluding chapters of his first volume, and to devote the second volume to the application of his principles to the interpretation of the geological record. He, however, found it impossible to include the chapters on changes in the organic world in the first volume and then decided to make them the opening portion of the second volume. It is evident, however, that as the work progressed, the interest of the various questions bearing on the origin of species grew in his mind. While Lyell found it impossible to accept the explanation of origin suggested by Lamarck, he was greatly influenced by the arguments in favour of evolution advanced by that naturalist; and as he wrote chapter after chapter on the questions of the modification and variability of species, on hybridity, on the modes of distribution of plants and animals, and their consequent geographical relations, and discussed the struggle of existence going on everywhere in the organic world, in its bearings on the question of 'centres of creation,' he found the second volume growing altogether beyond reasonable limits. His intense interest in this part of his work is shown by his remark, 'If I have succeeded so well with inanimate matter, surely I shall make a lively thing when I have chiefly to talk of living beings[58]?' By December 1831, Lyell had come to the resolution to publish the chapters of his work which dealt with the changes going on in the organic world as a volume by itself. This second volume of the _Principles_ he gracefully dedicated to his friend Broderip, who had rendered him such valuable assistance in all questions connected with Natural History.