230. We have already (Art. 203) been led to recognize the sun as the ultimate material source of all the energy which we possess, and we must now regard him as the source likewise of all our delicacy of construction. It requires the energy of his high temperature rays so to wield and manipulate the powerful forces of chemical affinity; so to balance these various forces against each other, as to produce in the vegetable something which will afford our frames, not only energy, but also delicacy of construction. Low temperature heat would be utterly unable to accomplish this; it consists of ethereal vibrations which are not sufficiently rapid, and of waves that are not sufficiently short, for the purpose of shaking asunder the constituents of compound molecules. 231. It thus appears that animals are, in more ways than one, pensioners upon the sun’s bounty; and those instances, which at first sight appear to be exceptions, will, if studied sufficiently, only serve to confirm the rule. Thus the recent researches of Dr. Carpenter and Professor Wyville Thomson have disclosed to us the existence of minute living beings in the deepest parts of the ocean, into which we may be almost sure no solar ray can penetrate. How, then, do these minute creatures obtain that energy and delicacy of construction without which they cannot live? in other words, how are they fed? Now, the same naturalists who discovered the existence of these creatures, have recently furnished us with a very probable explanation of the mystery. They think it highly probable that the whole ocean contains in it organic matter to a very small but yet perceptible extent, forming, as they express it, a sort of diluted soup, which thus becomes the food of these minute creatures. 232. In conclusion, we are dependent upon the sun and centre of our system, not only for the mere energy of our frames, but also for our delicacy of construction--the future of our race depends upon the sun’s future. But we have seen that the sun must have had a beginning, and that he will have an end. We are thus induced to generalize still further, and regard, not only our own system, but the whole material universe when viewed with respect to serviceable energy, as essentially evanescent, and as embracing a succession of physical events which cannot go on for ever as they are. But here at length we come to matters beyond our grasp; for physical science cannot inform us what must have been before the beginning, nor yet can it tell us what will take place after the end. FOOTNOTES: [10] _See_ an article on “The Position of Life,” by the author of this work, in conjunction with Mr. J. N. Lockyer, “Macmillan’s Magazine,” September, 1868; also a lecture on “The Recent Developments of Cosmical Physics,” by the author of this work. APPENDIX. CORRELATION OF VITAL WITH CHEMICAL AND PHYSICAL FORCES. BY JOSEPH LE CONTE, PROFESSOR OF GEOLOGY AND NATURAL HISTORY IN THE UNIVERSITY OF CALIFORNIA.