conceptions as to the place of utility in nature, far from proving that utility has been disregarded or sacrificed, shows that each organ has been formed, not only with reference to its actual use in a given individual or species, but to the capacity of being applied to use in countless other individuals and species.[25] [25] See Appendix XVII. When we enter into the examination of organisation in itself, adjustment becomes still more obvious in the processes of growth, reproduction, fructification, &c., in plants and animals, and in the provisions for locomotion, for securing food and shelter, for sight, hearing, &c., in the latter. The great physician, Sir Charles Bell, devoted a whole treatise to point out those which are to be found in the hand alone. The arrangement of bones, muscles, joints, and other parts in the limb of a tiger or the wing of an eagle are not less admirable. The eye and ear are singularly exquisite structures, the former being far the most perfect of optical, and the latter far the most perfect of acoustic instruments. Instances of this sort are, indeed, so remarkable, and so irresistibly convincing to most minds, that some theists have consented to rest on them exclusively the inference of a designing intelligence. They would grant that the evidences of purpose are only to be traced in organisation. The limitation is inconsistent and untenable, but not inexplicable. The adjustment of parts to one another, and their co-ordination as means to an end, are not more certainly existent in fitting the eye to see and the ear to hear than in securing the stability of the solar system, but they are more obviously visible because compressed into a compass easily grasped and surveyed; because organ and function are the most specialised kinds of means and ends; because organisms are the most curiously and conspicuously elaborate examples of order. And as the telescope can show us no end of the simple and majestic order of the heavens, so the microscope can show us no end of the exquisite and impressive order which discloses even-- "In Nature's most minute design, The signature and stamp of power divine; Contrivance intricate, expressed with ease, Where unassisted sight no beauty sees. The shapely limb and lubricated joint Within the small dimensions of a point; Muscle and nerve miraculously spun, His mighty work, who speaks and it is done. The Invisible, in things scarce seen revealed, To whom an atom is an ample field."--(COWPER.)[26] [26] See Appendix XVIII. The traces of a Supreme Reason crowd still more upon the vision when we come to the human mind,-- "The varied scene of quick-compounded thought, And where the mixing passions endless shift." --(THOMSON.)