Works of Grant Allen, page 790
CHAPTER VII.
THE ANIMAL ORGANISM.
In the last chapter we saw roughly what were the dynamical relations of those organisms which act mainly as accumulators of Energy. In the present one we must make a similar investigation regarding the dynamical relations of those organisms which act mainly as expenders or dissipators of Energy.
Amongst these, as already noticed, are many themselves of vegetal origin; and it may simplify matters if we first look briefly at their nature, afterwards noting the principal points of distinction between them and the animal organism proper.
A fungus grows upon a decaying tree. It has its origin in a spore; and this spore, alighting in the neighbourhood of previously-accumulated Energetic Compounds, has its own Energies liberated by heat and moisture; and thereupon becomes in turn a liberator of the Energies in the organised matter around it. These it gathers into its mass, and gradually dissipates, with the exception of that portion which it bequeaths to its spores, thereby once more beginning a similar cycle of changes. Wherever the fungus seats itself, — whether on the root or stem of a plant; or on a seed, tuber, or other receptacle of Energetic Compounds destined for future growth; or on an animal body; or on a patch of soil containing dispersed undecomposed organic matter; — it adds nothing to the total of Energy, being merely a dissipator of the Energy already accumulated.
Now, the animal organism is a mechanism in which these same processes take place, but take place much more rapidly and conspicuously, and are accompanied by certain secondary phenomena. As the highest organisms show all the processes of the lower, and also some others peculiar to themselves, it may be convenient to take an example from the upper ranks of animal life to illustrate the specialities of the case.
A young vertebrate begins its existence as a small mass of Energetic Compounds presenting elementary organisation, surrounded by another mass (more or less) of comparatively unorganised Energetic material. As in the case of the plant, the material may differ in amount, but must be sufficient, under the liberating agency of heat, to carry on the process of organisation to such a point that the young organism can obtain the necessary further material for itself. In the case of a bird, this material is supplied by the food-yolk; in that of a mammal it is supplemented by nutriment derived from the maternal circulating system. But in every case, the young plant and the young animal are alike in this, that each begins its life as an expender of previously-accumulated Energy. It is needless to add that the presence of free oxygen, which combines with the food-stuffs to produce carbonic anhydride, and so yields up its Energy for the act of organisation, is in both cases indispensable. So soon, however, as the self-sustaining degree of organisation has been reached, a wide difference begins to manifest itself. The plant spreads its leaves to the sun and the air, and drinks in carbonic anhydride and water, from which the ethereal Energy separates part of their oxygen, and manufactures starch and other organic compounds. The animal, on the contrary, devours the compounds thus formed, and drinking in the free oxygen, causes them to reaggregate within his body, using up the Energy so liberated, partly for the production of heat, partly for physiological processes, and partly for locomotion. What may be the exact nature of these conversions we do not fully know; and even if we did, they could only be detailed in a complete work on Physiology: but it is sufficient for our purpose to point out that Energetic carbonaceous and nitrogenous matters pass into the body by one channel, and free oxygen by another; that they leave the body as carbonic anhydride, ammonia, water, and other de-energised products; and that heat and motion have been given out meanwhile. The animal organism is thus essentially a seat for the reaggregation of matter and the dissipation of Energy. It is, however, probable that part of the Energy thus liberated is not immediately dissipated, but is used up for the time being in the so-called synthetic processes of the body. What these really are, we do not thoroughly understand: but it seems likely that they may be combinations of many atoms, possessing high relative Kinetic Energy, upon whose decomposition the Kinetic Energy is liberated. Thus, a manifestation of Energy accompanies the conversion of sugar into lactic acid, or into alcohol and carbonic anhydride, although no new oxygen is united during the process. At any rate, waiving all speculation, it is certain that these bodies, unlike ordinary compounds, possess Energy in their composite form, which is dissipated when they separate into simpler bodies.
While the animal lives, he is perpetually taking into his organism Energetic Compounds stored up in plants, or temporarily deposited in the tissues of other animals, and using up their Energies for his own activities. In some cases the matters thus absorbed are immediately employed for physiological processes: but in other cases they are stored up, like the starch and albumen of seeds or tubers, for future use. A bear living through the winter on his own fat, or a camel consuming his humps during a journey, is the exact analogue of the sprouting wheat and of the potato or hyacinth grown in a cellar. When the animal dies, heat and other animal germs act as liberators for his stored-up tissue Energies; and decomposition rapidly sets in, resulting in the final formation of stable compounds. Thus the matter which during the animal’s life possessed Energy of chemical separation in its atomic composition, — Energy of molar separation in its erect position and frequent elevation in the air or on mountain tops, — Energy of molecular motion in its heat, — and Energy of molar motion in its locomotive processes, — becomes at last a number of chemically stable masses, partly aggregated with the earth’s surface, and partly floating as carbonic anhydride, incapable of resuming its separate and self-moving condition except by the intervention of fresh solar Energy through the agency of vegetal life.
Viewed from a wide standpoint, we may say that animals act as liberating agents for the Energies stored up in plants. They are therefore links in that general chain of processes whereby separate portions of matter are made to aggregate in the stablest union, and their previously-existing separation is imparted to the ether.
CHAPTER VIII.
GENERAL VIEW OF MUNDANE ENERGIES.
We have now completed our brief survey of the cosmical facts known to us at present, and examined their congruity with our general theory of two opposing Powers, aggregative and separative. But before we close the subject it may be well to look briefly at the facts of mundane Energy in their entirety, with especial reference to the part played by man.
By the term ‘Cosmical Energies of the Earth’ we may understand all that Energy which our planet possesses in virtue of its statical separation from the sun and the other sidereal bodies. By the term ‘Proper Energies of the Earth’ we may designate all that Energy which the material particles composing the earth’s substance now possess or formerly possessed, in virtue of their own original separation from one another, as masses, molecules, or atoms. Finally, by the term ‘Derived Energies of the Earth,’ we may understand all that Energy which our planet has absorbed from the radiated Energy of other aggregating masses elsewhere: and as the amount of such absorbed Energy derived from the ‘fixed’ stars or reflected from the moon and planets is practically without conspicuous effects on the earth’s surface, we may consider this term as equivalent to directly incident solar Energy.
The Cosmical Energies need not long detain us. Doubtless, as the earth loses orbital Energy by ethereal friction, it is slowly approaching the sun, while the sun in turn is approaching its own central point of attraction; but these remote possibilities possess for man only a speculative interest, and have no influence on practical mechanical activities.
The Proper Energies of the Earth are more interesting to humanity. (1) First, come the facts of the planet’s orbital Energy and nutation, which indirectly yield the phenomena of winter and summer. (2) Next comes its axial motion (the indirect cause of day and night), of whose dissipation the tides are a concomitant. (3) More purely terrestrial are the phenomena of earthquakes, volcanoes, &c., which are Kinetic transformations of the statical separation existing between the superficial and central masses. (4) Derived from the last-named Energy is the Potential Energy of mountains and other masses raised by lateral pressure above the general level of the solid and liquid surface. In both these cases, — that of the whole cohering crust, and that of special raised masses — small portions of the Potential Energy become from time to time Kinetic under the influence of liberating agencies; in the first case, we know the result as an earthquake, in the second as a landslip. (5) Next may be mentioned the internal heat of the earth, small portions of which are always escaping by conduction through the cohering crust. (6) Lastly, we may mention the Potential Energy of chemical separation in free elements, like sulphur &c., within the earth’s crust, if these ought not to be regarded as of organic origin, and consequently included in the list of Derived Energies. All these Proper Energies are the surviving forms of the separation once existing between the various portions of our earth. (But in the case of the cohering crust, the mountains, and the free elements, the Energies remain as statical separations to our own time. In the case of the orbital and axial Energies, the separation has assumed the form of continuous molar motions. In the case of the internal heat, it has assumed that of continuous molecular motion.) And in every earthquake, landslip, falling cliff, or tumbling stone, we see these Potential Energies assuming the Kinetic Mode under our very eyes. Nor is it necessary to show in detail how the earth is gradually parting with all these Proper Energies. The orbital and axial motions are being dissipated by ethereal friction or by the moon’s attraction. The internal heat is being dissipated by conduction. The Potential Energy of the crust is being given up from time to time by earthquakes, or, after assuming the form of heat in volcanic eruptions, is being radiated off into ether. And the mountains, cliffs, and other elevated portions locally raised for awhile (to outward appearance) by these widespread disturbances, above the general level, are being for ever worn down by rain, storms, roots, animal footsteps, and other results of those Derived Energies which we have next to examine. So that the remaining Proper Energies of the earth (most of them having been long since dissipated, after the partial aggregation of its matter, during the cooling of its crust) are still being cast loose, in one form or another, upon the Energy-absorbing ether; while a corresponding aggregation of its matter is for ever taking place.
But the great mass of those Mundane Energies in which man is directly interested belong to the class of Derived Energies. And these, as we have already seen, may be considered as practically equivalent to the directly-incident solar energy and its derivatives. They are difficult to classify, owing to their rapid changes, but the following division may cast some light on their nature. Solar Energies are either Direct, as light and radiant heat, or Absorbed, as in clouds, organisms, &c. The latter or Absorbed class may be again divided into those of Inorganic Origin, and those of Organic Origin. Each of these will demand separate treatment.
Direct Solar Energy is the radiant Energy which from moment to moment is cast upon our planet from the sun. If the surface of the earth were composed of a perfectly reflecting non-absorbing substance, all this Energy would immediately be reflected back into space. As it is, a small portion is so reflected, but the greater part is absorbed by various superficial bodies in the production of motion and separation between their parts.
Absorbed Solar Energy, employed for Inorganic purposes, gives rise to the following among other phenomena. (1) The Energetic gaseous condition of the atmosphere. (2) The Energetic liquid condition of water in temperate climates. (3) The melting of ice. (4) The act of evaporation and raising of vapour. (5) The production of winds and storms. (6) The production of ocean currents. Some of these Energies are Kinetic, as in the case of the gases, liquids, &c.: but in other instances the Energy is rendered Potential for awhile, as in the case of the floating cloud, the head of water, and the ice or snow upon the mountain tops. And, finally, these Potential Energies are constantly becoming once more Kinetic, as when the rain falls, the river flows, and the glacier or avalanche slides down the valley. Each such Kinetic Energy is of course in the act of being dissipated, by friction or otherwise, to the ethereal medium. And as before noticed, these Inorganic Absorbed Energies become liberating agents for the proper Potential Energy of the Earth, when rain or rivers wear down rocks and mountains; when glaciers or avalanches grind their bed and tear away the stones; when storms beat the waves against the cliff; and when winds upset rocky masses. Moreover, they also act as liberating agents for Potential Energy of Organic Origin, when lightning, rain, or wind wears down and overthrows trees or buildings, when storms sink iron ships, and when avalanches overwhelm villages.
Still more difficult to trace, because of their numerous involutions, are the vicissitudes of that Energy which assumes the Organic form. Yet we must endeavour to give some account of its main phases. The Energy which falls on the growing plant lays up Energetic Compounds in the plant’s substance and raises it to a position of visible height. Part of the Potential Energy thus obtained, the plant uses up in its own processes: part remains for awhile inherent in its tissues. But, for the most part, sooner or later it is either devoured by an animal, or else dies. In the first case, the animal digests it, and uses up its Energy in its own processes as heat and motion. In the second case, fungi grow upon it, worms devour it, water disintegrates it, and in one way or another it yields up its Energy at last to ether. Besides the Energy thus stored up in existing organisms, there is some Energy belonging to extinct organisms yet remaining on our earth. The small amount which is stored up in wood, meat, Siberian mammoths, desiccated diatoms, and other like forms, may be neglected on account of its insignificant quantity. But there are considerable stores of Energetic material, known as coal, peat, rock-oil, &c., which deserve a passing mention. These are so situated that without a liberating agent they could not be dissipated. Such a liberating agent they find in man, who is so rapidly using them up that he is now beginning to look forward to a future when all such stores will be exhausted, and when he will have to depend for his stock of Energy on the immediate daily supplies from the sun. As to the animal organisms, they are themselves entirely expenders of Energy, and their whole life consists in a reaggregation of matter and consequent dissipation of Energy. In one way, however, such organisms leave portions of their Energy for awhile in a Potential form, namely by building. Every house, wall, church, &c., is a mass raised to a height by means of Energy: and it may retain its Energy, in the absence of a liberating agent, for a considerable time. But in the end, Solar Energy, in some one or other of its transformations, will act as a liberating agent to reduce these irregularities and wear down their masses. Either by rain, wind, fire, roots of trees, lightning, or the hand of man, every building sooner or later totters to the ground. And if it escapes all these, the earth’s own Proper Energy may prove its overthrow, by tides, earthquakes, subsidences, or volcanic eruptions. So that, as in every other case, we see the matter ultimately aggregating and the Energy handed over to the all-absorbing ether.
Thus the earth is for ever parting with its Energy in every shape. It is slowly aggregating with the sun and the fixed stars. It is losing its orbital and axial motions. By internal cooling, by subsidences, earthquakes, and volcanic eruptions, by radiation from lava and hot springs, it is getting rid of the proper separation and motion inherent in its own mass. Solar Energy falling upon it prevents and counteracts for awhile its total aggregation, — liquefies the ocean, keeps the atmosphere gaseous, creates winds and currents, piles ice on mountain-tops, stores up Energetic Compounds in vegetal and animal organisms, lays by coal and peat, builds castles and cathedrals, smelts iron, and separates chemical bodies in phials and jars. But this very same Solar Energy acts as a liberating agent in the long run not only for its own Potentially-Energetic products, but also for the proper Potential Energy of the earth. It wears down cliffs, mountains, and table-lands, it melts the ice and snow on the mountains, it sets the animal to devour the plant; it drives man to dig and burn the coal and petroleum; it overthrows the buildings he has piled; it rusts his iron implements; it corrodes his chemical reagents. In one way or another, all the Energy of the earth’s own primitive separation, and all the intercepted Energy of the sun’s primitive separation, go together to swell the Energy of the ether, the great waste-heap of the Universe.
The author is not disinclined to consider the ether as composed primordially of the most tenuous ponderable matter on the outside of all aggregating systems, to which therefore their Energy has been transferred, so as at last practically to neutralise the inherent Forces.
Falling in Love
WITH OTHER ESSAYS ON MORE EXACT BRANCHES OF SCIENCE
CONTENTS
PREFACE
FALLING IN LOVE
RIGHT AND LEFT
EVOLUTION
STRICTLY INCOG.
SEVEN-YEAR SLEEPERS
