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living being is analogous to a machine in this particular also.

Let us take the man who fires the rifle. We can trace back the motion of his forefinger to the contraction of a muscle; and we can go even further back and connect this contraction with a stimulus sent along the nerves from the brain, so that a material effect is here seen to be brought about by a material antecedent, just as truly as in an inanimate machine. Indeed, we may generalise, and say that, so far as we can physically investigate a living being, we may take it for granted that a material effect is due to a strictly material antecedent in his case also.

181. We have thus discussed two respects in which a living being is analogous to a machine, and the next point is to determine which of the two classes of machines most resembles the living being. Is he analogous to the solar system, a steam-engine, or a clock? or is he rather analogous to some delicately constructed machine, such, for instance, as a rifle? There can, we think, be no doubt that a living being most resembles a delicately constructed machine. For what is the characteristic of such a machine? It is that in it a comparatively great transformation of energy may be brought about by a comparatively small physical antecedent. Thus a slight breath of air may determine the fall of the egg off the table, or a slight tap the explosion of a large quantity of fulminating silver. So in the human being, a very small and obscure transmutation of energy in the mysterious brain-chamber may determine some very violent motion. 'Life is not a bully who swaggers out into the open universe, upsetting the laws of energy in all

directions, but rather a consummate strategist, who, sitting in his secret chamber over his wires, directs the movements of a great army."

182. Granting then that a living being is a delicately constructed machine, the next point is to determine what process of delicacy, what peculiar arrangement of unstable forces, is employed in his construction? Now it is very easy to perceive that the delicacy in this case is brought about by an unstable arrangement of chemical forces. It is plain that the body of an animal is a chemically unstable product, and if, as one consequence of this, great freedom of action and delicacy are possessed during life, it is another consequence that the extinction of life is very speedily followed by decay.

The body then owes its delicacy to its chemically unstable nature; to a peculiar collocation of particles which certainly would not, in virtue of their own merely physical forces, have united themselves together as we find them in the body.

183. To what, then, is due this peculiar grouping of particles in the living body?

We reply that it is, in one sense at least, derived from the food which is eaten. If animal food is eaten, it is of course derived from the body of the animal which is consumed. That animal may possibly have derived it from another animal, but more probably it has been derived in this case direct from the vegetable world. Ultimately, therefore, it is to this world that we must look as the source of that delicately constructed substance which plays such a wonderful and important part in the animal economy. If we go 1 Stewart on the Conservation of Energy.

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one link further back in the chain of causation, we shall be carried from the vegetable world to the sun as the great and ultimate physical source of that highclass energy and delicacy of construction which characterise vegetable products. It is, in truth, owing to the actinic rays of our luminary that vegetable tissue is manufactured in the leaves of plants, the carbonic acid of the air being decomposed, and oxygen given out, while the carbon, united with other substances, and modified thereby, is retained by the plant to form part of its substance, or perchance to become the food of animals.

184. We have therefore now arrived at the conclusion that the delicacy of construction which our frames require is ultimately derived from the sun, so far at least as the visible universe is concerned. If then we would reply to the question of this chapter, whether or not there may be beings superior to man connected with this present universe, let us look abroad and endeavour to ascertain whether there be in this universe any other obvious process of delicacy besides that which characterises the bodies of animals like ourselves.

Now, it has been pointed out that, in the atmospheric changes of this world, and more particularly of the sun, we have processes of great delicacy. It is believed that the positions of the planets Mercury and Venus affect the behaviour of sun-spots, and thus determine the conditions of atmospheric changes on the surface of our luminary that are absolutely overwhelming in their magnitude. We have only to reflect that a large sun-spot might swallow up fifty planets like our earth, and that some of the currents con

nected with it move at the rate of 100 miles per second, in order to realise the enormous scale of these solar outbreaks. Again, it is believed that the state of the solar surface with regard to spots determines the storms of our earth, so that hurricanes are most numerous in the Indian Ocean as well as on the coast of America during years of maximum sun-spots.1

But if such results are brought about by the relative positions of the planets of our system, it is evident that the cause is more analogous to the pulling of the trigger of a cannon ready to go off than to a downright blow. In fact, a vast transformation of energy in the sun is brought about by some obscure and illunderstood but comparatively trivial cause connected with the position of the nearer planets of our system. We have here a case where the magnitude of the effect is out of all proportion to that of the antece. dent; now this is, in other words, the definition of delicacy already given (Art. 179).

But, again, if delicacy of construction characterise the meteorological changes in the various members of our system, it is entirely absent from the orbital motions of these bodies. These want that great characteristic of delicacy, incalculability; for they are not only pre-eminently calculable, but are now calculated years beforehand as part of the regular business of the world. On the other hand, the meteorological changes of our earth and of the sun come upon us with all the abruptness characteristic of delicacy, and are eminently incalculable. The hurricane and the lightning flash are processes of Nature which man has in every age been prone to associate with personal 1 See Meldrum on the Periodicity of Rainfall.


intelligences. He has instinctively recognised the similarity between these abrupt and startling phenomena and the actions of an angry and powerful being.

185. It may no doubt be long since there has been anything like an extensive worship of the powers of nature amongst the civilised nations of the earth, but there may yet be found, even at the present day, especially amongst imaginative races, and in wild and mountainous regions, a lingering belief that personal agents are concerned in the more startling natural phenomena.

Such a belief was extensively prevalent during the middle ages, and whole volumes might easily be filled with an account of medieval superstitions and legends relating to this subject, sometimes dark and terrible, and at other times possessing a peculiar and pathetic beauty which does not belong to anything else. The air, the earth, and the water have all been peopled with spirits; some of them friendly to man, some of them his deadly enemies. They are powerful, and conscious of their power, but at the same time profoundly and mournfully aware that they are without a soul. Their life depends, it may be, upon the continuance of some natural object, and hence for them there is no immortality. Sometimes, however, an elemental spirit procures a soul by means of a loving union with one of the human race, and the beautiful romance of Undine is built upon this fancy.

At other times the reverse happens, and the soul of the mortal is lost who, leaving the haunts of men, associates with these soulless but often amiable and affectionate beings. 'The Forsaken Merman,' by

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