another, whether such operation be necessary or voluntary, nor how they may stand disposed either to comfort or torment us. 9. In either case our condition will be determined by the objects accosting us, and company we fall into. We are here luckily situated in an organization enabling us to help ourselves to the conveniences and enjoyments of life, but when turned out of this we know not where to find such another, nor how to get into any other at all. Though surrounded with dangers on all sides, we have sense and experience to avoid them, but when divested of our sense and experience, we may be like a blind man turned out into a crowded street, having nothing but chance to direct our steps, insensible of mischiefs before they fall upon us, and unknowing which way to escape them. We may be tossed about among the elements, driven by streams of air, or whirled round in circles of fire, the little corpuscles of light may hurt us, and the ether teaze us with its continual repulsion: in short, we have everything to fear and little to hope for. Thus the discovery of our durable and perceptive nature affords no comfort, for while we confine our contemplation to that, the prospect lies dismal, dark, and uncertain before us. Let us then turn our thoughts upon external nature, in order to discover what rules and powers there may be governing that, in hopes of learning something how they may affect us, and in what manner we are likely to be disposed of. CHAP. VII. EFFECTS AND CAUSES. THOUGH We are all convinced of our short continuance in this present state, we are well satisfied that the course of nature will not be interrupted by our departure: the sun will still rise and set, the tides ebb and flow, the trees continue to bear their fruits, the cattle to multiply, the earth to yield her increase, and the business of mankind to go forward, after we are dead and gone. But the contemplation of these things gives us no instruction how to provide for our future accommodation, nor furnishes us with any light to discover what accommodations may be provided to our hands. Shall we heap up riches? those we must leave behind, or could we carry them with us, our money would not pass current in the other world. Shall we plant gardens or breed up numérous flocks? their produce will not suit our digestion. Shall we raise a family or spread our fame amongst mankind? we may not remember our own names, nor have an intercourse with the living to know what they say of us. Shall we improve knowledge and cultivate the sciences? our ideas may be totally different, and our sciences unintelligible to us. Shall we rectify our dispositions of mind, and lay in store of virtues? these are habits wherein the animal circulation is concerned, nor can we be sure they shall continue when that is removed from us. Shall we be careful to nourish the little body that is to serve us for our next habitation, to invigorate its limbs and quicken its organs? we know not where they lie, nor what we can do to improve their growth. And as we can do nothing of ourselves, so neither have we assurance of anything that will be done for us: we know not what nests shall be provided to hatch us into life, nor what parents we shall have to protect our tender infancy, and teach us the learning necessary for our conduct; what sustenance the air may afford, or where to find it, or whether we shall want any sustenance at all; what variations of weather may prevail in the ether answering to the pleasing warmth of a vernal sunshine, or the storms and inclemencies of winter, nor how to shelter ourselves from the latter. The subtile fluids causing gravitation, cohesion, electricity, and magnetism, may strike our new senses instead of lights, sounds, savors, and odors, and fill us with agreeable or troublesome sensations. We may meet with different species of animals proportionable to our size, answering to ravenous birds and beasts of prey or such as serve for our uses in life. We may fall into societies of fellow-creatures among whom we may find friends and enemies, who may give mutual delight by their conversation, or vex one another with their contrariety of tempers and opposition of interests. Since then we can find nothing certain by considering the constitution of particular things, let us search for the general laws prevailing throughout all nature for perhaps we may see that their influence must occasion some resemblance or similar tendency in the municipal laws of the several regions of nature, and we may discover some methods of conduct whereby to put ourselves in a situation to receive benefit and escape damage from that influence. But as those laws depend upon the causes operating in the productions of nature, we must endeavor to investigate the causes from their effects discernible to our senses or discoverable by our reason. 2. We may distribute our prospect of nature into three parts, primary qualities, motion, and situation, which concur in every operation we see or can think of. When a cannon-ball dashing into a heap of sand disperses it all about, the situation into which the particles are thrown, follows from their several situations in the VOL. I. 57 heap and the contact or propinquity of the ball when striking, from the violent motion wherewith it struck, and from its solidity to give, and their own solidity to receive, an impulse. So the growth of plants is owing to the near situation of nutritious particles in the earth that bears them, the position of their little parts in fibres and tubes fitted for containing the sap, to the action of sun and air, and to the properties of matter whereon that action depends. Nor is the case different with respect to the acts of free agents, which cannot proceed without a close situation of that which is to be the subject of their action or object of their perception, nor could their organs take a different modification whereby to exhibit different ideas without a motion in their parts, nor could anything be perceived or done without perceptibility and mobility in body, or perceptivity and motivity in spirit. And there are three causes commonly observed in the phenomena we see, Chance, Necessity, and Design. When the wind drives about the seeds of thistles, they fall in particular spots by chance; where they light, the peculiar contexture of their parts makes them necessarily produce plants of their own species; and when we cul'tivate and dress our ground, sow our corn, keep it weeded, and harvest it, we proceed by design. 3. I shall begin with the consideration of motion without which the courses of nature cannot be carried on: but this we may satisfy ourselves is not a quality of body, which is a moveable but no more a moving than a quiescent substance, being alike indifferent to either state, and continuing in either until put out of it by some foreign force. We see bodies moved by other bodies striking or shoving against them, but the mover gives no more motion than it had itself before, and always loses so much as it has imparted to another. And though motion sometimes seems to proceed from the pressure of quiescent bodies, there is always some external impulse occasioning the pressure; for two bodies meeting with equal force in opposite directions, after having stopped one another, will lie forever close together, gently touching, but not pressing each other unless something pushes or strikes against them on the outside. It is true we see motion frequently produced without discerning the cause, but then experiment and reason assure us that bodies never produce motion, but only transmit it by an impulse arising from their natural property of persevering in a motion once received. Thus, while we confine our thoughts to matter, it will appear that every motion is the product of some preceding motion, transferred from body to body, and incapable of increase by the translation. That there is an inexhaustible source of impulse somewhere, though undiscernible : by our senses, we may rest assured when we consider the dissolving power of menstruums, the violence of fire, the strong contraction of our heart and arteries, the stability of heavy masses held down by gravitation to the earth, and the firm cohesion of metals all which must have some prodigious fund, we know not where to find, from whence to derive the force they exert. It seems not improbable there may be streams of a most subtile matter much finer than ether itself darting incessantly along in all directions with inconceivable velocity: that the solid parts of quiescent bodies lie in the spaces between these streams, which likewise throw and preserve the atoms in their longitudinal position of wire before supposed, that upon the touch of fire thrusting any of the particles aside into the streams, it dashes them about against other particles, driving these likewise upon other streams, and so causes that explosion we find in gunpowder. Just as if an army were marching briskly along in very wideranks, another army in like loose array might march quietly between them but if a few men were pushed into the others' ranks, it would cause a violent commotion and tossing to and fro among them. We may help ourselves a little in this idea by considering a cube of glass hung up between candles on all the six sides of it, the rays would pass continually through without being stopped by the glass or jolting against one another; and this whether the glass remained still or were swung to and fro; but if by a smart blow the parts of the glass were to change their position, forming a multitude of little cracks, it would become opaque and not afford them a passage, in which case if the streams of light were strong enough they must rend the glass into atoms and keep buffeting them about until by frequent tossings they had brought them to lie in the interstices between themselves. : 4. It may seem at first sight impossible that such streams of subtile matter should be able to run in all directions without stopping or jostling one another: but let us consider that we find by experience the same thing happens in the passage of light. Hang a multitude of candles round the room and you shall be able to see any one of them distinctly through the light of all the hemisrest. The stars scattered about in all parts of the upper phere find their way to our eyes, but they must traverse many miles of thick solar radiance before they can come to that shadow of the earth which makes our night: and their rays falling upon the of other persons my eyes must cross those falling upon a mile around me in a variety of angles: yet all this without any stoppage or deviation from their course, for if they were at all af eyes fected by the other rays they pass through, it must cause perpetual refractions and we should see them dance about like so many Will-i'the-whisps. But what makes the difficulty in this case is our conceiving the rays of light to be so many continual streams like those of water, the parts touching close upon one another, whereas it has been observed in CHAP. III. that the corpuscles composing a ray of light may possibly keep a distance of `a hundred and sixty miles behind the next preceding them, though they follow so exceeding quick that we think their impulse upon our optics continuous. Now the particles of subtile matter, being much smaller and swifter than those corpuscles, their bulk may be estimated to bear an infinitely less proportion to the spaces between them than a ship does to the length of one hundred leagues. Let us then imagine ships to sail from every port in Europe to America and others from every port in America to Europe, each ship a hundred leagues behind that which parted last from the same port, and their courses be ordered in such manner as that they should cross over one particular spot of the ocean: those ships would so rarely fall foul of one another as to make no perceivable interruption in commerce; why then may not the little particles be allowed to collide so seldom as to cause no disturbance or interruption in the courses of nature. Another difficulty springs from the extreme minuteness of those particles, which can hardly be thought capable of holding bodies together in such strong cohesion as we experience in metals: but let us remember that the momentum given by all mechanical powers is found by a compound ratio of their quantity of matter and velocity, so that any deficiency in the former may be made up by a proportionable increase of the latter. Nor need we wonder that very small agents should produce great effects, since we know that the burst of a cannon will shake a whole street, but the particles of air giving immediate impulse to the houses can scarce be supposed to weigh many grains. The like appears in explosion of gunpowder where the quantity of matter operating is a very trifle in comparison with the heavy masses it raises and compact bodies it rends. I shall only remark further that this subtile matter, being the cause of gravitation, cohesion, and repulsion, in other bodies, can neither gravitate, nor cohere, nor repel itself; because it will want a prior cause to give it those qualities: nor has it other power than that of impinging like a stone, by virtue of the prodigious velocity wherewith it darts along. Nevertheless, we may count it the primum mobile, or first material agent in all the operations of nature, as driving her two main wheels of attraction and repulsion, from whence all the |