more satisfactory object to contemplate, than gun-powder with an immaterial repulsive virtue, that is, with an intangible soul in charcoal and minerals. And thus, by parity of reason, we must think, that in all departments of Nature, an effect with an impelling cause is a lesser difficulty than motion without impulse. I see no reason for inventing other subtile matters in succession without end, to account for the motions of the first. When I get to the subtile matter of fire, it is not requisite that I should go farther. If you should ask me, what gives this force to fire? I must answer the question by another; what makes the sun shine? What but the power of the Creator, for whose pleasure all things were created, and to whose laws all Nature is obedient? Philosophy searches after his instruments; Theology asserts his power; but Human Wisdom will never be able to settle the mode of its influence.

What I have hitherto said, will, I hope, be sufficient to give an idea of the object, the matter, and the argument, of that introductory publication, by which I endeavoured to remove the first of my difficulties, the supposed demonstration of an unmechanical constitution of Nature, by our excel-" lent

c 2

-lent Newton; whose demonstrations, so far as they extend, no man can oppose, without being justly suspected of ignorance or presumption.

Great as my first difficulty might appear, I thought my second greater; and I found it so: because we know what is required of us when we are answering an argument; but no man can tell when he shall have satisfied a blind suspicion. All I can say is this: that if it should have been my lot to suffer under any false imputations, as many better men have done before me; and if I have been suspected of being led by incompetent authority into any opinions, either unprofitable or indefensible; the work I now offer must be my answer. This second book will shew what I had in view when I published the first. It will shew, that in every subject I treat of, I take my own ground, and work upon it in my own manner. It will shew, that I use every writer so far as he can assist me, while I take part with none. Many have been the commentators on philosophy, and none in the world so happy and successful in every part of it as those of our own country: plures una gens eximios tulit in quocunque genere, quam ceteræ terræ: but

still, NATURE is the text; and where there is difference of opinion, and authority seems to be against me, then I must plead that text, as a good protestant pleads his Bible.

The subjects I treat of are, the Elements of the World, their natures, properties, powers, and effects; which are the genuine. objects of physiological inquiry, and open to us so large a fund of entertainment and improvement, that the sagacity of a Newton, if he were to live a thousand years, would never be able to exhaust it. It will be concluded, and very justly, that, in the prosecution of this study, I have been much in→ debted to the learned collections and discoveries of the Royal Society, of which I have the honour to be a member. I ought likewise to own, that, before I entered upon the business of experimenting for myself, I derived much information from the useful and extensive lectures on philosophical chemistry, by the late Dr. Alcock, in the University of Oxford: I should have been happy if he had lived to receive this testimony of my gratitude. A few select memoirs of his life were published in the last year, which cannot be perused with indifference by those who knew him, and were interested in the transactions

of his time.But now it will be

proper to say something of the manner in which I have treated the subjects of the present volume.

There are four distinct forms of Philosophy-mythological, systematical, experimental, and sacred; all of which must be applied to, as sources of information, by those who wish to understand the science of Natural Philosophy in its proper extent; as I have endeavoured to do, that I might place my work upon a broader foundation, and render it more generally useful.

The MYTHOLOGICAL form of philosophy is to be found in the theology of the Heathen priests, poets and philosophers. Their deity was the visible system of Nature; and their particular divinities, male and female, were the separate powers, agents and operations of the world. They supposed Nature to be eternal and self-moved, and sensible of men's words and actions; therefore they fell into the custom of representing Natural Philosophy under the mystical form of religious fable. True and rational Philosophy undertakes to make plain the wonders of Nature: but the mythologic form was invented to turn plain things into wonders, and give them an oracular dignity, to preserve them

from

from the contempt of the vulgar. They who had no spiritual mysteries, or believed none, converted Natural Philosophy into mystery, and gave it the air of a divine revelation. The mysteries of the Hebrews related to a Theocracy, that is, to the intercourse of God with man: the mysteries of the Heathens to Physiocracy; for such we may call that constitution of the world, which gives the supreme government to the powers of Nature itself. I could illustrate what I here advance, by multiplying testimonies from writers of all ages; but this is occasionally done in the work itself. A fashion prevailed in the last century, of converting the fables of Gentilism into true history, on a supposition that they all took their rise from events related in the Scripture. In this attempt Bochart and Huet were leaders, and the erudition expended in it was immense, without any sensible benefit to the Christian, or the learned world. Lord Bacon, who is generally to be trusted in his ideas of literature, has some excellent observations on the fables of the ancients, and applies them for the most part according to their true physical' intention but he intermixes rather more of the moral than was intended by the fabrica€ 4

tors