Mr. Darwin tells us, in the preface to his last edition of the “Origin of Species,” that Lamarck was partly led to his conclusions by the analogy of domestic productions. It is rather hard to say what these words imply; they may mean anything from a baby to an apple dumpling, but if they imply that Lamarck drew inspirations from the gradual development of the mechanical inventions of man, and from the progress of man’s ideas, I would say that of all sources this would seem to be the safest and most fertile from which to draw. Plants and animals under domestication are indeed a suggestive field for study, but machines are the manner in which man is varying at this moment. We know how our own minds work, and how our mechanical organisations—for, in all sober seriousness, this is what it comes to—have progressed hand in hand with our desires; sometimes the power a little ahead, and sometimes the desire; sometimes both combining to form an organ with almost infinite capacity for variation, and sometimes comparatively early reaching the limit of utmost development in respect of any new conception, and accordingly coming to a full stop; sometimes making leaps and bounds, and sometimes advancing sluggishly. Here we are behind the scenes, and can see how the whole thing works. We have man, the very animal which we can best understand, caught in the very act of variation, through his own needs, and not through the needs of others; the whole process is a natural one; the varying of a creature as much in a wild state as the ants and butterflies are wild. There is less occasion here for the continual “might be” and “may be,” which we are compelled to put up with when dealing with plants and animals, of the workings of whose minds we can only obscurely judge. Also, there is more prospect of pecuniary profit attaching to the careful study of machinery than can be generally hoped for from the study of the lower animals; and though I admit that this consideration should not be carried too far, a great deal of very unnecessary suffering will be spared to the lower animals; for much that passes for natural history is little better than prying into other people’s business, from no other motive than curiosity. I would, therefore, strongly advise the reader to use man, and the present races of man, and the growing inventions and conceptions of man, as his guide, if he would seek to form an independent judgement on the development of organic life. For all growth is only somebody making something.