so insignificant a part in the great scheme of nature' should have been created. And this is written in the language of theologico-natural-history rather than from the point of view of one who realises the full meaning of the struggle of existence.
After reading the 'Journal' of 1845 we come back with a sense of surprise to the Manuscript Sketch of 1844, where his theory of evolution by means of natural selection is so completely given. Even in the note-book filled between July 1837 and February 1838 the views on evolution are striking in their completeness; thus he clearly believed in the common origin of animals and plants. The book is filled with detached notes, often taking the form of a query, as to the bearing of his views on such points as classification, geographical distribution, geological time, and the relation of fossil to modern forms, rudimentary organs, extinction, isolation, means of transport, &c.
The idea of natural selection is not prominent in the 1837-8 note-book, but it is suggested in such a sentence as the following: 'With respect to extinction we can easily see that [the] variety of [the] ostrich, [the] Petise, may not be well adapted and thus perish out; or on [the] other hand, like Orpheus [a bird], being favourable, many might be produced. This requires [the] principle that the permanent variation produced by confined breeding and changing circumstances are continued and produce[d] according to the adaptations of such circumstances, and, therefore, that [the] death of [a] species is a consequence ... of non-adaptation of circumstances.' The sketch of 1844 bears, on the whole, a striking resemblance to the origin of species, in the kind of points treated, in the arrangement of the argument, and in the choice of illustrations, and even some of the sentences are almost identical. It is not to be expected that it should bear the stamp of matured consideration, or the control and balance arising from an accumulated wealth of fact and thought, and this difference is perceptible. What Darwin himself believed to be the great flaw in the 1844 sketch was want of the ' principle of divergence ' (see Origin of Species 6th ed.) By those who are imbued with evolution as taught in the 'Origin of Species,' this 'principle of divergence will hardly be missed in reading the sketch of 1844; we seem unconsciously to assume the principle, although it is not given. In his later years Darwin had something of this feeling, for it became all but incredible to him that he should at first have overlooked it. We have some evidence of the estimate which Darwin formed of the 1844 sketch at the time. A letter exists, addressed to his wife, in which he made provision, in case of his death, for the publication of the manuscript. After stating that he believes his conclusions to be ' a considerable step in science ' he goes on to request that a sum of 400l. or 500l. shall be given to an editor who, with the help of his books and notes, should undertake to correct and expand and illustrate the sketch. The idea that the sketch might be left as the only record of his work must have remained in his mind for many years, for the following note is pencilled on the back of the letter, with the date August 1854: ' Hooker by far best man to edit my species volume.'
During the years between 1844 and 1858 (when he began to write the ' Origin of Species ') he read enormously, going over whole series of periodicals, books of travel, on sport, general natural history, horticulture, and on the breeding of animals, so that, as he expressed it, he was afterwards surprised at his own industry. And it should be remembered that he was carrying out this laborious undertaking without being buoyed up by any very certain hope of converting others to his views. Thus he wrote to Sir J. D. Hooker in 1844: 'In my most sanguine moments all I expect is that I shall be able to show ... that there are two sides to the question of the immutability of species.' Then, too, there was much practical and experimental work to be done. He prepared skeletons of many kinds of domesticated birds, and minutely compared the size and weight of their bones with those of the wild species. He also began in 1855 to keep tame pigeons and to make laborious crossing experiments, Then there was a long inquiry, both by experiment, reading, and correspondence, into the means of transport of seeds, which entailed trials as to the powers of floating and of resisting salt water possessed by a large number of fruits and seeds. His letters contain long discussions with Sir Charles Lyell, Sir Joseph Hooker, and Dr. Asa Gray, on a variety of geological questions, on geographical distribution, or on the theory of 'large genera varying' (which latter point required much laborious tabulation of various Floras), on the hypothetical continents of Edward Forbes, and on a host of other points.
Such work as this was steadily continued, and would perhaps have been indefinitely prolonged, had it not been for the interference of his friends. In 1856, at the urgent advice of Lyell, he determined to write out his results. Lyell wished him to prepare a preliminary volume, but he seems to have found this an impossibility, and in July 1856 he wrote: 'I have resolved to make it [the book]
