rebound against the mechanical theory of the universe, which held imperious sway during the thirty years that followed Darwin's first great attempt at systematisation. The influence of Darwin, and Spencer, and perhaps even more, of Huxley and Tyndall, of Haeckel and Weismann, had led to a belief that physics and physiology between them solved everything. Now a good many people go to the other extreme, and assert that they have solved nothing. And the scientists themselves, though they have not abandoned the nineteenth century conceptions of force, matter, and development, are anxious to supplement them by pushing their enquiries into the psychic region. Science itself cannot deal with the facts it has discovered without travelling beyond force and matter and development. It has to postulate something else, something in the nature of mind, and something beyond that; something which is not matter nor force, and yet can act upon both. So it begins to join hands with religion, and reluctantly suggests that there may be such a thing as a spiritual power, operating outside the limits of space and time."

Before we proceed, let us pause to do honour to those men and women who, though ignorant of the facts of science, had heard what science was supposed to have proved and yet held steadfastly to their faith through years of storm. They were not dismayed at the supposed results of scientific progress because they had faith, and faith is so far above intellect that, unlike the latter, it never suffers confusion. We are not, however, now concerned to discover what information can be gained from the lives of saintly people; our business is to discuss what may be learned from scientific investigation.

§ 2. Purpose of the Paper.-In discussing the modern conception of the universe, I shall endeavour to examine how far that conception leads to or is consistent with the idea of an almighty Creator having a just claim to the obedience and worship of men. We must not expect that the testimony of science, unaided by spiritual insight, can lead to anything more than the simplest form of religion, but if it does go so far the testimony is of immense value. If men grasped no more than the idea of the existence of an almighty Creator and allowed its significance to have a place in their lives, the gain would be very great.

But this paper is not intended to be in any way an apology for religion. I shall merely endeavour to set down, as simply as possible, some of the conclusions to which modern scientific investigation unhesitatingly points. The survey will, however,

be incomplete, for it will be necessary to omit all but a bare mention of the moral and spiritual feelings and experiences of men, though these are phenomena of the universe, just as much as any physical or chemical actions, and generally lead to actual events in the world of matter, as, for instance, when a call to the mission field leads to the transport of a human body, with clothes and books, across the ocean.

One of the greatest needs at the present day is, I believe, an insistence on the idea of God as the Creator of the universe. If this idea were more forcibly brought home to the minds and consciences of men, they would perhaps pay more attention to religion generally. If the influence of religion has appeared to suffer at the hands of science, it has been mainly because many have been led to an attitude of doubting through the suggestion that scientific investigation has left no place for a God as the Creator of the world. With this doubt in their hearts, it is easy for men to profess the opinion that there are no such things as God's laws to be obeyed or to be broken.

But it is becoming more and more plain that so far from science leading to any such conclusion, the facts all point in the opposite direction, and thus science is more and more bearing testimony to the fundamental article of religion. We may here quote Lord Kelvin's statement* that "if you think strongly enough, you will be forced by science to believe in God, which is the foundation of all religion."

§ 3. The Universe and Human Thought.-It should be noted, before we go further, that the essential character of the universe does not depend in the least upon our intellectual conceptions, for the universe remains the same whatever may be our individual views concerning it. It is important to bear this in mind, because some persons, who have not grasped the distinction between an hypothesis and a fact, are in danger of imagining that these great questions are settled by the pronouncements of the popular speaker who is fashionable at the time. The distinction between fact and hypothesis must be continually remembered in discussing scientific discoveries, for, apart from the inevitable errors of observation, the simplest experiment is in reality so complex an affair that we can do no more than frame an hypothesis which will account for its main features. Yet, if the hypothesis is verified when the experiment is repeated under a variety of conditions, it acquires a high degree of credibility. That is all that we can say.

* Nineteenth Century, June, 1903, p. 1068.

Those who are much occupied with literary work are exposed to the danger of treating realities as if they were merely subjects for academic discussion. In physics, however, there is so constant an appeal to experiment, either directly or through mathematical reasoning, that students of physics are to a considerable extent freed from this danger, and in biology experiment is now rescuing that science from the thraldom of opinion. But in regard to theological studies, it is perhaps true to say that mere opinion has in some cases been allowed a position which does not belong to it. Thus many assert that miracles never happened, the only ground for the assertion being their opinion that they are impossible. Much would be gained if it were realised that what occurred in the past is not in the least affected by the opinions of persons, however exalted, who live in the twentieth century.

There is a popular notion that some strange impersonal thing called Modern Science has examined the universe in the cold light of experiment and has arrived at infallible conclusions. But this is not a true picture. for there is no one of the conclusions of modern science which can be said to be absolutely established, and the utmost that can be said of any conclusion is that the experiments are in approximate agreement with it. It is true that some conclusions become more and more firmly established as the accuracy of the experiments is increased, but, on the other hand, an increase of accuracy sometimes requires us to modify a conclusion. A striking example is furnished by the discovery of the gas argon in the atmosphere. In spite of an old experiment of Henry Cavendish, it was believed that atmospheric air was a mixture of oxygen, nitrogen, carbonic acid gas and water vapour, with very small additions of other known gases. But the accurate work of Lord Rayleigh and Sir W. Ramsay showed that more than one per cent. of what was supposed to be nitrogen was the previously unknown gas argon, and this has led to the detection of other gases.

§4. The Complexity of the Universe.-In the earlier stages of scientific progress it was to some extent possible to divide science into branches and to contine attention to one branch at a time; it was possible to attend to the phenomena exhibited in one or more bodies without much regard to the relations between those bodies and the rest of the universe. But modern investigation makes it logically impossible to work any longer in water-tight compartments, and is gradually leading us to appreciate the fact that the number of actions to which every particle in the universe is continually subject is very great.

One instance will show how the progress of discovery compels a wider outlook. Newton accounted for the motions of the planets and their satellites by the law of gravitation, and the work of subsequent mathematicians and astronomers has abundantly verified his formula in the case of bodies of considerable mass. But recent investigation has verified the theoretical prediction of Maxwell that, when one of the bodies is intensely heated, as the sun is, the stream of radiant energy which falls upon the second body exerts a force upon it. As the second body becomes smaller, this force rises in importance relative to the force due to gravitation till at length it rivals and surpasses it, and it follows that the motions of those particles of cosmical dust, which are scattered through space, depend not only upon the action of gravitation, as was formerly supposed, but also upon the pressure of radiation.

Modern discoveries have led us to a point of view from which we are compelled to regard every particle in the universe as continually subject to a great variety of actions, though of course at any given instant some actions may be more strongly in evidence than others, and thus we realize that the history of even a single molecule, considered as a whole, is one of great complexity.

The evidence of the spectroscope indicates that each molecule has a very complex structure. Thus, each line in the spectrum of a substance corresponds to one mode of vibration of the molecules, and in the spectra of some substances, such as iron, hundreds of these lines may be counted. But the molecules are not merely complex in themselves; they have very complex connexions with their surroundings. Thus oxygen can combine with nearly all the other chemical elements either singly, as in the case of hydrogen in the formation of water, or in groups, as in the case of hydrogen and sulphur in the formation of sulphuric acid. The total number of such combinations is enormous. Thus we may say that each element is so constructed as to respond to the influence of each of the great majority of the other elements, and to a great number of their compounds. Of recent years the discovery of radio-active. substances has greatly raised our estimate of the complexity of molecules.

When we combine the complexity of each molecule with the vastness of the number of molecules in the world of stones and trees and men and sun and stars, and consider that each molecule acts on every other one, the complexity of the conception is enough to make us despair of further progress. But science

has not stopped here, and has not left us without some sign-posts to guide us in our perplexity. I shall now endeavour to indicate some results obtained from experimental work which lead to conceptions shedding a little light upon the nature and character of the universe.

$ 5. Nature of Matter.-In the bodies around us, on the earth or in the sky, whether they be inanimate or whether they be living organisms of any kind, we see a bewildering variety of substances. But the labours of chemists have led to the belief that all bodies are built up of a comparatively small number of elements, such as oxygen, carbon, or iron, and have shown that, if the elements be arranged in a series according to a certain law, there are very remarkable relations between the properties of an element and its place in this series. The existence of gaps in this series was thought to indicate that some elements remained to be discovered, and the theory of the series enabled the general character of the missing elements to be clearly described. The predictions have been confirmed by the actual discovery of some of the missing elements. These results of chemical science at once simplify our ideas about the material bodies around us, for instead of thinking of countless millions of different substances we need only think of about one hundred. That the elements found on the earth occur in the sun and stars is shown by the spectroscope and by chemical analysis, which proves that many meteorites which have fallen on the earth are almost identical in composition with the most deep-seated terrestrial rocks.

In the case of helium, the existence of the gas was first revealed by spectroscopic examination of the sun, in whose spectrum a line was found which did not correspond to any terrestrial element then known; the name of helium was given to the element causing the line. Helium has now been found in terrestrial minerals, and has been liquefied by Kammerlingh Onnes at Leiden, the temperature of the liquid being only three or four degrees above the absolute zero of temperature. This extremely low temperature, the lowest reached, so far, in any experiments affords a strange contrast to the temperature of 5000° Centigrade or more which prevails in the sun, where helium was first discovered.

The numerical relations between the elements suggest that they are all built up of some primordial substance. The most promising speculation is that which regards a molecule as consisting of a larger or smaller number of minute parts, separated by relatively large distances, these parts being