but harm to any human being. And so died the science of the old world, in a true second childhood, just where it began.

The Jewish sages, I hold, taught that science was probable; the Greeks and Romans proved that it was possible. It remained for our race, under the teaching of both, to bring science into act and fact.

Many causes contributed to give them this power. They were a personally courageous race. This earth has yet seen no braver men than the forefathers of Christian Europe, whether Scandinavian or Teuton, Angle or Frank. They were a practical hard-headed race, with a strong appreciation of facts, and a strong determination to act on them. Their laws, their society, their commerce, their colonisation, their migrations by land and sea, proved that they were such. They were favoured, moreover, by circumstances, or (as I should rather put it) by that divine Providence which determined their times, and the bounds of their habitation. They came in as the heritors of the decaying civilisation of Greece and Rome; they colonised territories which gave to man special fair play-but no more in the struggle for existence, the battle with the powers of nature; tolerably fertile, tolerably temperate; with boundless means of water communication; freer than most parts of the world from those terrible natural phænomena, like the earthquake and the hurricane, before which man lies helpless and astounded, a child beneath the foot of a giant. Nature was to them not so inhospitable as to to starve their brains and limbs, as she has done for the Esquimaux or Fuegian; and not so bountiful as to crush them by her very luxuriance, as she has crushed the savages of the tropics. They saw enough of her strength to respect her: not enough to cower before her; and they and

she have fought it out; and it seems to me, standing either on London Bridge or on a Holland fendyke, that they are winning at last.

But they had a sore battle: a battle against their own fear of the unseen. They brought with them, out of the heart of Asia, dark and sad nature-superstitions, some of which linger among our peasantry till this day, of elves, trolls, nixes, and what not. Their Thor and Odin were at first, probably, only the thunder and the wind: but they had to be appeased in the dark marches of the forest, where hung rotting on the sacred oaks, amid carcases of goat and horse, the carcases of human victims. No one is acquainted with the early legends and ballads of our race, but must perceive throughout them all the prevailing tone of fear and sadness. And to their own superstitions they added those of the Rome which they conquered. They dreaded the Roman she-poisoners and witches, who, like Horace's Canidia, still performed horrid rites in graveyards and dark places of the earth. They dreaded as magical the delicate images engraved on old Greek gems. They dreaded the very Roman cities they had destroyed. They were the work of enchanters. Like the ruins of St. Albans here in England, they were all full of devils, guarding the treasures which the Romans had hidden. The Cæsars became to them magical man-gods. The poet Virgil became the prince of necromancers. If the secrets of nature were to be known, they were to be known by unlawful means, by prying into the mysteries of the old heathen magicians, or of the Mohammedan doctors of Cordova and Seville; and those who dared to do so were respected and feared, and often came to evil ends. It needed moral courage, then, to face and interpret fact. Such brave men as Pope Gerbert, Roger Bacon, Galileo, even Kepler,

did not lead happy lives; some of them found themselves in prison. All the mediæval sages-even Albertus Magnus-were stigmatised as magicians. One wonders that more of them did not imitate poor Paracelsus, who, unable to get a hearing for his coarse common sense, took-vain and sensual-to eating the opium which he himself had discovered and vaunted as a priceless boon to men; and died as the fool dieth, in spite of all his wisdom. For the 'Romani nominis umbra,' the shadow of the mighty races whom they had conquered, lay heavy on our forefathers for centuries. And their dread of the great heathens was really a dread of nature, and of the powers thereof. For when the authority of great names has reigned unquestioned for many centuries, those names become, to the human mind, integral and necessary parts of nature herself. They are, as it were, absorbed into her; they become her laws, her canons, her demiurges and guardian spirits; their words become regarded as actual facts-in one word, they become a superstition, and are feared as parts of the vast unknown; and to deny what they have said is, in the minds of the many, not merely to fly in the face of reverent wisdom, but to fly in the face of facts. During a great part of the middle age, for instance, it was impossible for an educated man to think of nature herself, without thinking first of what Aristotle had said of her. Aristotle's dicta were nature; and when Benedetti, at Venice, opposed in 1585 Aristotle's opinions on violent and natural motion, there were hundreds, perhaps, in the universities of Europe there certainly were in the days of the immortal Epistolæ Obscurorum Virorum-who were ready, in spite of all Benedetti's professed reverence for Aristotle, to accuse him of outraging not only the father of philosophy, but nature

herself and her palpable and notorious facts. For the restoration of letters in the fifteenth century had not at first mended matters, so strong was the dread of nature in the minds of the masses. The minds of men had sported forth, not toward any sound investigation of facts, but toward an eclectic resuscitation of Neoplatonism, which endured, not without a certain beauty and use as let Spenser's Faery Queen bear witness-till the latter half of the seventeenth century.

After that time a rapid change began. It is marked by-it has been notably assisted by - the foundation of our own Royal Society. Its causes I will not enter into; they are so inextricably mixed, I hold, with theological questions, that they cannot be discussed here. I will only point out to you these facts: that, from the latter part of the seventeenth century, the noblest heads-the noblest hearts, too-of Europe, concentrated themselves more and more on the brave and patient investigation of physical facts, as the source of priceless future blessings to mankind; that the eighteenth century, which it has been the fashion of late to depreciate, did more for the welfare of mankind, in every conceivable direction, than the whole fifteen centuries before it; that it did this good work by boldly observing and analysing facts; that this boldness toward facts increased in proportion as Europe became indoctrinated with the Jewish literaure; and that, notably, such men as Kepler, Newton, Berkeley, Spinoza, Leibnitz, Descartes, in whatsoever else they differed, agreed in this, that their attitude toward nature was derived from the teaching of the Jewish sages. I believe that we are not yet fully aware, how much we owe to the Jewish mind, in the gradual emancipation of the human intellect.

The connection may not, of course, be one of cause and effect; it may be a mere coincidence. I believe it to be a cause; one of course of very many causes, but still, an integral cause. At least the coincidence is too remarkable a fact, not to be worthy of investigation.

I said, just now-The emancipation of the human intellect. I did not say-Of science, or of the scientific intellect; and for this reason:

That the emancipation of science is the emancipation of the common mind of all men. That all men can partake of the gains of free scientific thought, not merely by enjoying its physical results, but by becoming more scientific men themselves. Therefore it was, that though I began my first lecture by defining superstition, I did not begin my second by defining its antagonist, science. For the word science defines itself. It means simply knowledge; that is, of course, right knowledge, or such an approximation as can be obtained; knowledge of any natural object, its classification, its causes, its effects; or in plain English, what it is, how it came where it is, and what can be done with it.

And scientific method, likewise, needs no definition; for it is simply the exercise of common sense. It is not a peculiar, unique, professional, or mysterious process of the understanding: but the same which all men employ, from the cradle to the grave, in forming correct conclusions.

Every one who knows the philosophic writings of Mr. John Stuart Mill, will be familiar with this opinion. But to those who have no leisure to study him, I should recommend the reading of Professor Huxley's third lecture on the origin of species.

In that he shows, with great logical skill, as well as with some humour, how the man who, on rising in the morning, finds the

parlour window open, the spoons and teapot gone, the mark of a dirty hand on the window-sill, and that of a hob-nailed boot outside, and comes to the conclusion that some one has broken open the window and stolen the plate, arrives at that hypothesis (for it is nothing more) by a long and complex train of inductions and deductions, of just the same kind as those which, according to the Baconian philosophy, are to be used for investigating the deepest secrets of nature.

This is true, even of those sciences which involve long mathematical calculations. In fact, the stating of the problem to be solved is the most important element in the calculation; and that is so thoroughly a labour of common sense that an utterly uneducated man may, and often does, state an abstruse problem clearly and correctly; seeing what ought to be proved, and perhaps how to prove it, though he may be unable to work the problem out, for want of mathematical knowledge.

But that mathematical knowledge is not-as all Cambridge men are surely aware-the result of any special gift. It is merely the development of those conceptions of form and number which every human being possesses; and any person of average intellect can make himself a fair mathematician if he will only pay continuous attention-in plain English, think enough about the subject.

There are sciences, again, which do not involve mathematical calculation; for instance, botany, zoology, geology, which are just now passing from their old stage of classificatory sciences into the rank of organical

selves of the conclusions of these sciences, may add to these conclusions fresh and important discoveries; and if I am asked for a proof of what I assert, I point (in spite of assertions in it from which I differ) to Rain and Rivers, written by no professed scientific man, but by a colonel in the Guards, known to fame only as one of the most perfect horsemen in the world.

solid contents of the valley, are all that are needed. The method is that of science; but it is also that of simple common sense. You will remember, therefore, that this is no mere theory or hypothesis, but a pretty fair and simple conclusion from palpable facts; that the probability lies with the belief that the glen is some hundreds of thousands of years old; that it is not the observer's business to prove it further: but other persons' to disprove it, if they

can.

He has, at first sight, a very simple measure that of denudation. He sees that the glen is now being eaten out by a little stream, the product of innumerable springs which arise along its sides, and which are fed entirely by the rain on the moors above. He finds, on observation, that this stream brings down some ten cubic yards of sand and gravel, on an average, every year. The actual quantity of earth which has been removed to make the glen may be several million cubic yards. Here is an easy sum in arithmetic. At the rate of ten cubic yards a year, the stream has taken several hundred thousand years to make the glen.

You will observe that this result is obtained by mere common sense. He has a right to assume that the stream originally began the glen. because he finds it in the act of enlarging it;-just as much right as he has to assume, if he finds a hole in his pocket, and his last coin in the act of falling through it, that the rest of his money has fallen through the same hole. It is a sufficient cause, and the simplest. A number of observations as to the present rate of denudation, and a sum which any railroad contractor can do in his head, to determine the

The observer, if he be a cautious man, begins to see if he can disprove his own conclusion; moreover, being human, he is probably somewhat awed, if not appalled, by his own conclusion. Hundreds of thousands of years spent in making that little glen! Common sense would say that the longer it took to make, the less wonder there was in its being made at last: but the instinctive human feeling is the opposite. There is in menthere remains in them, even after they are civilised, and all other forms of the dread of nature have died out in them-a dread of size; of vast space; of vast time— that latter, mind, being always imagined as space, as we confess when we speak instinctively of a space of time. They will not understand that size is merely a relative, not an absolute term; that if we were a thousand times larger than we are, the universe would be a thousand times smaller than it is; that if we could think a thousand times faster than we do, time would be a thousand times longer than it is; that there is One in whom we live, and move, and have our being, to whom one day is as a thousand years, and a thousand years as one day. I believe this dread of size to be merely, like all other superstitions,

a result of bodily fear, a development of the instinct which makes a little dog run away from a big dog. Be that as it may, every observer has it; his own conclusion seems to him strange, doubtful—he will reconsider it.

Moreover, if he be an experienced man, he is well aware that first guesses, first hypotheses, are not always the right ones; and if he be a modest man, he will consider the fact that many thousands of thoughtful men in all ages, and thousands still, would say, that the glen can only be a few thousand, or possibly a few hundred years old. And he will feel bound to consider their opinion; as far as it is, like his own, drawn from facts: but no further.

So he casts about for all other methods by which the glen may have been produced, to see if any one of them will account for it in a shorter time.

1. Was it made by an earthquake? No; for the strata on both sides are identical, at the same level, and in the same plane.

2. Or by a mighty current? If so, the flood must have run in at the upper end, before it ran out at the lower. But nothing has run in at the upper end. All round above are the undisturbed gravel beds of the horizontal moor, without channel or depression.

3. Or by water draining off a vast flat as it was upheaved out of the sea? That is a likely guess. The valley at its upper end spreads out like the fingers of a hand, as the gullies in tide-muds do.

But that hypothesis will not stand. There is no vast unbroken flat behind the glen. Right and left of it are other similar glens, parted from it by long narrow ridges; these also must be explained on the same hypothesis: but they cannot. For For there could not have been surface drainage to make them all, or a tenth of them. There are no other possible

hypotheses; and so he must fall back on the original theory-the rain, the springs, the brook; they have done it all, even as they are doing it this day.

But is not that still a hasty assumption? May not their denuding power have been far greater in old times than now?

Why should it? Because there was more rain then than now? That he must put out of court: there is no evidence of it whatsoever.

Because the land was more friable originally? Well, there is a great deal to be said for that. The experience of every countryman tells him that bare or fallow land is more easily washed away than land under vegetation. And no doubt, when these gravels and sands rose from the sea, they were barren for hundreds of years. He has some measure of the time required, because he can tell roughly, how long it takes for sands and shingles left by the sea to become covered with vegetation. But he must allow that the friability of the land must have been originally much greater than now, for hundreds of years.

But again, does that fact really cut off any great space of time from his hundreds of thousands of years? For when the land first rose from the sea, that glen was not there. Some slight bay or bend in the shore determined its site. That stream was not there. It was split up into a million little springs, oozing side by side from the shore, and having each a very minute denuding power, which kept continually increasing by combination as the glen ate its way inwards, and the rainfall drained by all these little springs, was collected into

the one central stream. So that when the ground being bare was most liable to be denuded, the water was least able to do it; and as the denuding power of the water increased, the land, being covered with vegetation, became more and