So these in their first contact with the cold air begin to resist and not to wish to pass further forward; the others below continue to rise; the part above being stationary proceeds to thicken; the warmth and dryness recede to the centre; the part above abandoned by the warmth begins to freeze or rather to dissolve; the clouds below continue to rise and press the warmth nearer to the cold; and thus the warmth being constrained to return to its primary element is suddenly transformed into fire and twines itself across the dry vapour, and in the centre of the cloud makes a great increase, and kindling within the cloud which has become cool it makes a noise that resembles that of water falling on boiling pitch or oil, or of molten copper when plunged into cold water; even so, driven out by its opposite it shatters the cloud that would withstand it and dashing through the air breaks and destroys everything that opposes it; and this is the thunderbolt.
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Where the flame cannot live no animal that
draws breath can live
The bottom part of the flame is the first origin of this flame and through it passes all its nutriment of fat; and it is of less heat than the rest of the flame, just as it is of less brightness; and it is blue in colour and here its nutriment is purged and disposed of. The other part has the brighter flame, but this is the first to come into existence when the flame is created and it is born in spherical shape, and after a span of life produces above itself a very small flame of radiant colour and shaped like a heart, with its point turned towards the sky; and this continues to multiply towards infinity by absorbing the substance that feeds it.
The blue flame is formed of spherical shape . . . and does not in itself form a pyramidal figure until it has warmed the surrounding air sufficiently; and the principal heat of this blue flame goes upwards in the direction where it is the natural desire of the blue flame to travel, that is the shortest way to the sphere of fire.
The colour of the blue flame does not move of itself. Nor does the nourishment given to the flame by the candle move of itself. The movement must therefore be generated by others. The generator of this movement is the air which rushes to refill the vacuum created by the air that had been previously consumed by the flame. The light generates vacuum, and the air runs to succour this vacuum.
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5. MICROCOSM AND MACROCOSM
The organic and inorganic worlds are both of similar nature and subject to the same natural laws. Man is a part of a world, a microcosm included in a macrocosm.
The Beginning of the Treatise on Water
Man has been called by the ancients a lesser world and indeed the term is well applied. Seeing that if a man is composed of earth, water, air, and fire, this body of earth is similar. While man has within himself bones as a stay and framework for the flesh, the world has stones which are the supports of earth. While man has within him a pool of blood wherein the lungs as he breathes expand and contract, so the body of the earth has its ocean, which also rises and falls every six hours with the breathing of the world; as from the said pool of blood proceed the veins which spread their branches through the human body, so the ocean fills the body of the earth with an infinite number of veins of water. . . .
In this body of the earth is lacking, however, the nerves, and these are absent because nerves are made for the purpose of movement; and as the world is perpetually stable, and no movement takes place here, nerves are not necessary. But in all other things man and the earth are very much alike.
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Explanation of the presence of water on the
summits of the mountains
I say that just as the natural heat of the blood in the veins keeps it in the head of man, and when the man is dead the cold blood sinks to the lower parts, and as when the sun warms the man’s head the amount of blood there increases and grows so much with other humours, that by pressure in the veins it frequently causes pains in the head; in the same way with the springs which ramify through the body of the earth and, by the natural heat which is spread through all the containing body, the water stays in the springs at the high summits of the mountains. And this water that passes through a pent-up conduit within the body of the mountain like a dead thing will not emerge from its low state because it is not warmed by the vital heat of the first spring. Moreover, the heat of the element of fire and by day the heat of the sun have power to stir up the dampness of the low places of the mountains and to draw them up in the same way as it draws the clouds and calls up their moisture from the bed of the sea.
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The same cause which moves the humours in all kinds of living bodies against the natural law of gravity also propels the water through the veins of the earth wherein it is enclosed and distributes it through small passages. And as the blood rises from below and pours out through the broken veins of the forehead, as the water rises from the lowest part of the vine to the branches that are cut, so from the lowest depth of the sea the water rises to the summits of mountains, where, finding the waves broken, it pours out and returns to the bottom of the sea. Thus the movement of the water inside and outside varies in turn, now it is compelled to rise, then it descends in natural freedom. Thus joined together it goes round and round in continuous rotation, hither and thither from above and from below, it never rests in quiet, either in its course or in its own nature. It has nothing of its own but seizes hold on everything, changing into as many different natures as there are different places on its course, acting just like the mirror which takes in as many images as there are things passing in front of it. So it changes continually, now as regards place, now as regards colour, now it absorbs new smells or tastes, now it detains new substances or qualities, now it brings death, now health, sometimes it mixes with air or lets itself be drawn on high by heat, and on reaching the cold region, the heat that guided it upward is squeezed by the cold. And as the hand presses the sponge under water where the water flowing out makes an inundation into the other water, so the cold presses the air that is mingled with water, making it flee in fury and drive the other air; this then is the cause of the wind.
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That which to the utmost admiration of those who contemplate it raises itself from the lowest depth of the sea to the highest summits of the mountains and pouring through the broken veins returns to the deep sea and again rises with swiftness and descends again, and so in course of time the whole element circulates. So from high to low, so passing in and out, now with natural movement, now with fortuitous movement it proceeds, together and united. So it goes ranging round in continual circulation after the manner of the water of the vine, which as it pours through its cut branches and falls upon its roots rises again through the passages and falling again returns in continual circulation.
The water which sees the air through the broken veins of the high mountain summits is suddenly abandoned by the power which brought it there, and escaping from these forces resumes its natural course in liberty.
Likewise the water that rises from the low roots of the vine to its lofty head falls through the cut branches upon the roots and mounts anew to the place whence it fell.
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6. A SPIRIT AMID THE ELEMENTS: ITS LIMITATIONS
Of Spirits
We have said that the definition of a spirit is a power united to a body, because of itself it can neither rise nor take any kind of movement in space, and if you say that it does rise of itself this cannot be within the elements. For if the spirit is an incorporeal quantity, this quantity is called a vacuum, and the vacuum does not exist in nature; and granting that one were formed it would be immediately filled up by the rushing in of the element in which such a vacuum had been generated. Therefore, by the definition of weight, which says that gravity is an accidental power, created by one element being drawn or impelled towards another, it follows that any element without weight in one element acquires weight by passing into the element above it, which is lighter than itself. One sees that a part of water has neither gravity nor levity when merged in the other water, but will acquire weight if drawn up into the air; and if you were to draw the air beneath the water, then the water on finding itself above this air acquires weight, which weight it cannot support by itself, and hence its collapse is inevitable; and it will fall into the water at the spot where there is a vacuum. The same thing would happen to a spirit if it were amid the elements where it would continually generate a vacuum in whatever element it might find itself and for this reason it would be continually flying towards the sky until it had quitted those elements.
Whether the spirit has a body amid the elements
We have proved that a spirit cannot of itself exist amid the elements without a body, nor can it move of itself by voluntary motion except to rise upwards. We now say that such a spirit in taking a body of air must of necessity mingle with this air; because if it remained united the air would be separate and fall when the vacuum is generated, as is said above; therefore it is necessary if it is to be able to remain suspended in the air, that it should absorb a certain quantity of air; and if it were mingled with the air, two difficulties ensue, namely that it rarefies that portion of the air wherewith it mingles and for this reason the rarefied air will fly upwards of its own accord and will not remain among the air that is heavier than itself; and, moreover, that as this spiritual essence is spread out it becomes separated and its nature becomes modified, and it thereby loses some of its first power. Added to these there is a third difficulty, and that is that this body of air taken from the spirit is exposed to the penetrating winds, which are incessantly sundering and tearing to pieces the united portions of the air, revolving and whirling them amid the other air; therefore the spirit which is infused in this air would be dismembered or rent and broken up with the rending of the air into which it was incorporated.
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Whether the spirit having taken a body of air,
can move of itself or no
It is impossible that the spirit infused into a certain quantity of air should have power to move this air; and this is proved above where it is said that the spirit rarefies that portion of the air wherein it has entered; therefore such air will rise above the other air, and this movement will be made by the air through its own lightness, and not through the voluntary movement of the spirit, and if this air is encountered by the wind, by the third part of this discourse, the air will be moved by the wind and not by the spirit diffused in it.
Whether the spirit can speak or no
Wishing to prove whether or no the spirit can speak it is necessary first to define what voice is, and how it is generated; and we shall describe it thus: The voice is movement of air in friction against a dense body, or of a dense body in friction against the air—which is the same thing; and this friction of the dense with the rare condenses the rare and causes resistance; moreover the rare when in swift motion, and the rare moving slowly condense each other at their contact, and make a noise or great uproar; and the sound or murmur caused by one rare moving through another rare at a moderate speed is like a great flame which creates noises in the air. And the loudest uproar made by one rare with another is when the one moving swiftly penetrates the other which is motionless; as for instance the flame of fire issuing from a big gun striking the air; and also like the flame issuing from the cloud which strikes the air and so produces thunderbolts.
Therefore we may say that the spirit cannot produce a voice without movement of the air, in it there is none and it cannot emit what it has not; and if it desires to move the air in which it is diffused it becomes necessary that the spirit should multiply itself, and that cannot multiply which has no quantity. And in the fourth part it is said that nothing rare can move unless it has a stable spot whence to take its motion; and much more so in the case of an element moving in its own element, which does not move of itself, except by uniform evaporation at the centre of the thing evaporated: as occurs with a sponge squeezed in the hand which is held under water; the water escapes from it in every direction with equal movement through the openings that come between the fingers of the hand in which it is squeezed.
Whether the spirit has articulate voice, and whether the spirit can be heard, and what hearing is and seeing, and how the wave of the voice passes through the air and how the images of objects pass to the eye.
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There can be no voice where there is no motion or percussion of the air; there can be no percussion of the air where there is no instrument; there can be no instrument without a body; this being so a spirit can have neither voice, nor form, nor force; and if it were to assume a body it could not penetrate nor enter where the doors are closed. And if any should say that through air collected together and compressed a spirit may assume bodies of various forms, and by such instrument may speak and move with force—to him I reply that where there are neither nerves nor bones there can be no force exerted in any movement made by imaginary spirits.
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