time ago a noted chemist, then well advanced in years, remarked to the author that in his youth he could boast that he knew the whole of Chemistry as it was then known, but that no youth of to-day could hope to say the same. This remark referred to one branch of Science alone, so it goes without saying that the most learned scientist of to-day cannot possibly know the whole of Science. What, then, of the average person who cannot devote his life to study?A formidable list of sciences—Their real relationship—Is a little learning a dangerous thing?—The day of specialists—The building of the great edifice of science—Its beginning in the long-ago—Different ways of discovering things—Man's knowledge.
Not many of us would undertake to write down from memory even the names of all the sciences, while for the meaning of some of the names not a few people of ordinary intelligence would require to consult a dictionary. We should have no difficulty in writing down:—Astronomy, Anatomy, Anthropology, Archaeology, Biology (which includes both Botany and Zoology), Geography, Geology, History, Meteorology, Philosophy, Physiology, Psychology, Sociology, and Theology. Then we might follow with the names of some sciences which end in the letters "ic" or "ics," such as:—Ethics, Logic, Mathematics, Mechanics, Metaphysics, Politics, and Physics. And those of us who are more interested in Science might add: Cosmology, Embryology, Epistemology, Histology, Hexicology, Morphology, Ornithology, Paleontology, and Philology. After that we might name a few of the branches or sub-divisions: Acoustics, Algebra, Arithmetic, Chemistry, Crystallography, Dermatology, Dynamics, Electricity, Ethnology, Etiology, Etymology, Geometry, Hydraulics, Ichnology, Ichthyology, Metallurgy, Mineralogy, Magnetism, Optics, Pneumatics, Statics, and many others.
No apology is required to accompany the statement that this volume does not profess to cover the whole field of Science. But there is another object in putting down this formidable list of sciences. We must not look upon the different sciences as we might picture so many separate or individual buildings—not even as so many rooms in one great building, but rather as different parts of one great room.
If one examines this list of sciences it is quite apparent that each interpenetrates another. Any person commencing the study of one particular branch of Science will find that he has entered other branches also. It has been said that to know any one branch of Science is to possess a private door into the whole realm of Nature.
If we wish to make a serious study of Science we must select one subject, or even one branch of that subject. On the other hand, there is a great interest in taking a wider view of Science. One so often hears the words of Pope—"a little learning is a dangerous thing"—being used where they do not apply. There is no danger whatever in learning the general principles involved in any branch of Science without learning all the detail. Perhaps if this fact were more generally recognised there would be more real knowledge acquired by our young people.
The present is the day of Specialists, and there can be no doubt that in the future it will become more and more necessary to specialise. It is the natural outcome of the accumulation of knowledge which man has been building up, and with what a quickening pace is the edifice now arising! But we must not run away with the idea that all the actual building has been done in these modern times. While these islands of ours were peopled with ignorant and semi-barbarous natives, learned men were at work in the East, and had it not been for the serious study of these students of long-past ages the edifice of Science could not have reached its present proportions. As Macaulay has said:
"Every generation enjoys the use of a vast hoard bequeathed to it by antiquity, and transmits that hoard, augmented by fresh acquisitions, to future ages."
In the long-ago, Science was confined to the few "wise-men" in each generation, and even in quite recent times Science was considered "dry stuff" so long as its story was to be found only in scientific textbooks. But now that Science has been applied to such a great extent in our everyday life, it attracts in some measure the attention of all thinking persons. The lad who studies Science instead of sensational novelettes has much more real pleasure in his reading.
In his presidential address to the British Association for the Advancement of Science, in 1909, Sir J. J. Thomson said:—"I think a famous French mathematician and physicist was guilty of only slight exaggeration when he said that no discovery was really important or properly understood by its author unless and until he could explain it to the first man he met in the street."
Our present subject is Scientific Discovery, and it is obvious that things may be discovered in several different ways. Professor Roentgen was surprised to discover the X-rays while he was experimenting with some vacuum tubes.
In one sense his discovery was accidental, but only in a qualified sense, as we shall see later.
But some great discoveries have been made in the same sense as a gold-digger discovers the gold for which he is searching. M. and Mme. Curie were searching deliberately for a radioactive substance when they discovered Radium.
The discovery of electric waves, or what some people think of as "wireless waves," was also the result of a deliberate search. Their existence had been predicted many years before they were discovered. The youthful German professor, Heinrich Hertz, had no doubt whatever of the existence of electric waves, and he succeeded in devising means by which he could discover their whereabouts.
Yet another kind of discovery is illustrated by the experience of the ancient mathematician Archimedes, who was born about three hundred years before Christ. Most of us heard the story of Archimedes while we were still in the nursery, or at least before we could understand how his plunging into a bath could enable him to discover whether the king's crown was made of pure gold, or whether the goldsmith had cheated the king by stealing some of the gold given to him and substituting silver in its place. We knew that the discovery must have been of great importance or Archimedes would not have rushed shouting through the streets to his own home without waiting to dress. These particular discoveries, mentioned here by way of illustration, will be dealt with in later chapters. Our present purpose is to note that all discoveries are not made in the same way.
It must be quite evident that man has discovered everything he knows concerning this planet on which he lives; concerning the great Universe in which his planet is but a little thing; and concerning himself and every existing thing. We wish to consider how some of his great discoveries have been made, and the most natural point to set out from is the world in which he finds himself.