Therefore, when the news of the invention of Gutenberg reached the scholars of Italy and other lands, they seized upon it as an undreamed-of blessing for bringing about that widespread study of the classical authors which they had been struggling under so many difficulties to accomplish.

To narrate and describe the progress made since then in the art of printing would be to rewrite what has been written from time to time in books and magazines and papers. To describe and point out the other arts that have sprung directly from the art of printing, such as the manufacture of printing presses and allied machinery, would require an enormous book of a wholly technical nature; to describe and point out the arts that have been made necessary, and the arts that have been made possible, by the invention of printing would entail a history of most of the industrial arts of the present day; while to mention and adequately describe the measures that have resulted from the invention of printing, and those made necessary and possible by it, would entail a history of all the civilization that has come into being since printing was invented.

The effects of the invention of printing are most of them so obvious that it would be unnecessary to call attention to them. No other one art seems to be so directly and clearly to be credited with the progress of civilization. In the minds of many people, perhaps of most people, printing is considered the most important invention ever made. Maybe it is; but let us remind ourselves that the gun came before the printing-press, and that the civilization contributed to by the printing press would not have been possible without the gun. It may be answered that, nevertheless, the printing press contributed more than the gun; in the same way that a bank contributes more to the welfare of a city than does the policeman who guards the bank.

Such an argument would have much to commend it, and it may be based on the correct view of the situation. But to the author, the gun seems to constitute the foundation of modern civilization, and the printing press to be part of the structure built upon it; for the fundamental enemy to civilization has always been the barbarian, be he a savage under Attila or a Bolshevik in New York. It is true that civilization may be considered as more important than the means that makes it possible, but even this seems to be discussible; but that the gun constitutes more distinctly the preservative influence of modern civilization than any other one thing constitutes civilization itself seems hardly to be discussible. The whole system of defense of all the nations against foes outside and anarchy inside has rested on the gun ever since it was invented; whereas, not even the printing press can be said to be the only element, or even the main element, in modern civilization.

This brief discussion is perhaps not very important; but it does not wholly lack importance, for the reason that it brings into clear relief the fact that we cannot reasonably discuss civilization without realizing the dangers that confront it, and have always confronted it, and will continue to confront it. Civilization is an artificial product, that some people think has more evil in it than good for the majority of mankind, and that certainly has been forced on mankind by a very small minority. The foundation on which the force has rested for four hundred years has been the gun.

But whatever the comparative amount of influence of the gun and the printing press, there can be no doubt that they have worked together hand in hand: that one guarded, and the other assisted, the first tottering steps of the Renaissance movement, and that both have continued to guard and assist the grand march that soon began, and that is still advancing.

As the circumstances surrounding the invention of both the gun and the art of printing are sufficiently well known to warrant the belief that each was made, not by a king or any other man of high position, but by a man relatively obscure, and that the surroundings and early life of both were not those of courts or palaces, but those of a humble kind, it may be well to note how enormous are the results that have flowed from causes that seem to be very small. We have been told that "great oaks from little acorns grow"; but the consequences that have grown from the conception of the idea of printing are larger than any oak; and an acorn is probably much larger than the part of the brain in which an idea is conceived.

As a matter of interest, let us realize the strong resemblance between the impression we receive from a material object actually seen by the eye and the memory of that impression afterwards. Let us then realize the strong resemblance between it and another impression of that same object seen mentally but not physically; for instance, let us realize the strong resemblance between the impression made on us by actually seeing some friend and the impression received by imagining him receiving a letter which we are now writing to him. The first picture was an image of the external object that was physically made on the retina, as a picture or image is made by a camera on a screen; but that picture on the retina must have been seen by the brain, or we would not have known of it. The other pictures were not made physically on the retina, so far as we know. Yet we all realize that we can make pictures on our minds the more readily if we close our eyes. The fact of our eyes being open seems to operate adversely to our receiving a clear mental picture.

Now it is a matter of fact that an object (for instance, a pole) can be seen by a person with normal eyesight, if it subtends an angle as great as one minute; that a pole a foot thick can be seen clearly from a distance of 3600 feet, at which distance it subtends that angle. The rays of light pass through the crystalline lens of the eye and are focussed on the retina, as they pass through the lens of the camera, and are focussed on the sensitized paper. Assuming the distance from the crystalline lens to the retina to be about three-quarters of an inch, the pole would be represented on the retina by an image 3/(4 x 3600) or less than 1/4000 of an inch wide. During daylight our retinas are continually receiving images of which all lines as wide as 1/4000 of an inch (and much narrower) are very clearly apprehended by the mind.

But very few of those images are noticed by us. It is only when some incident calls them to our attention, or when the mind voluntarily seizes on them, that any conscious impression is made upon the brain. Similarly, images of physical objects unseen by the physical eye are continually made on the mind: we are continually thinking of our friends and of past incidents and possible future incidents; and our thoughts of these things take the form of pictures. We see the man with whom we had a conversation yesterday, and we see him with a clearness that is proportional to the interest taken by the mind in the conversation and the circumstances surrounding it. If our conversation was uninteresting and the circumstances tame, we see him dimly. But if our conversation was angry and the circumstances were exciting, we see him and the surroundings very vividly—so vividly that our anger is again aroused; perhaps to as high degree as on the day before, or even higher.

This image-making is, of course, voluntary sometimes; but most images come without volition on our part, and require no effort that we are conscious of. To call up an image voluntarily requires conscious effort; and to keep it in position while we gaze upon it requires effort that is great in proportion to the time during which it is exerted. Psychologists speak of this act of keeping an image in position as one of giving attention, or paying attention.

To perform this act requires the exercise of will, unless the act gives pleasure, or the image suggests danger; in each of these cases, of course, the act is almost involuntary.

A man who is observant notes consciously the incidents that are passing around him: he seizes on certain of the millions of pictures passing before him, concentrates their images on his retina, and gazes on each one for a while. Similarly, a man who is contemplative, seizes on certain of the vague mental pictures passing through his mind, concentrates his attention on them, and gazes at each one for a while. We call the former an observant man and the other a thoughtful man. Sometimes an observant man learns a great deal from what he sees, in the same way that sometimes a studious man learns a great deal from what he studies; but the learning of course cannot be accomplished without the assistance of the memory. One is often surprised to see how little some observant and studious men have remembered. Many impressions have been received, but few retained.

The thoughtful man, of course, cannot in the nature of things receive so many conscious impressions as the merely observant or studious man; for the reason that he continually seizes on one and then another, and holds each for a time, while he fixes his attention on it. Usually, however, the thoughtful man memorizes his observations or his studies for some specific purpose; he moves the various images about in his mind; and arranges them in classes: for otherwise, the various images would form merely an aggregation of apparently unrelated facts. The value of such aggregations is, of course, enormous; they compose what we call data, and include such things as tables of dates, etc.

But data, even tables of dates, have no value in themselves; it is only from their relations to other things that they have value. There would be no value, for instance, in knowing that William of Normandy invaded England in 1066, unless we knew who William was, and what England was, and what the effect of his invading it was. Now the thoughtful man, like the man who arranges a card-catalogue in such a way that it will be useful, not only notes isolated facts, but puts them into juxtaposition with each other, and sees what their relations are. The mental pictures that he finally fixes in his mind are of related things, seen in their correct perspective. They are like the pictures which are made on the mind of anyone by—say, a landscape: whereas the mental pictures made by an unthoughtful man are such as little children probably receive from nature; pictures in which the trees and hills and valleys of a landscape do not appear as such, but merely as a great aggregation of numberless separate images, confused and meaningless like the colored pieces of a kaleidoscope.

To the thoughtful man, therefore, life seems not quite so meaningless as to his neighbor; though even the most thoughtful can fix very few complete and extensive pictures in his mind. If his thoughtfulness takes him no further than simply forming pictures that enable him to see things as they are, and in their correct relations to each other, he becomes "a man of good judgment," a man valuable in any community, especially for filling positions in which the ability to make correct deductions is required.

Such a man, however, no matter how correctly he may estimate any situation, no matter how clearly he may see all the factors in it, no matter how accurately he may gauge their relative values and positions, may be unable to suggest any way for utilizing its possible benefits, or warding off its possible dangers. That is, he may lack constructiveness. He is like a man who possesses any desirable thing or dangerous thing, and who understands all there is to understand about it, but does not know what to do with it. The various factors are in his (mental) hands, but he can make nothing of them.

The constructive man can construct concrete entities out of what are apparently wholly individual factors having no relation to each other; he can, for instance, take two pieces of wood and a piece of string, and make a weapon with which he can kill living animals at a considerable distance. With neither the pieces of wood nor the string could he do that; and he could not do it with all three, unless he were able to construct them into a bow and arrow. That is, he could make the weapon if he had ever seen it made before. If he were only constructive and not inventive, he could not make it unless he had seen it done before, or knew it had been done.

Men of purely constructive ability have not of themselves taken very conspicuous parts on the stage of history; and yet the things that they have constructed comprise nearly all that we can see and hear and touch in the world of civilization. Thus history, while it is a narrative of things that have been done, is not a narrative of all the things that have been done, but only of the new and striking things. It is a narrative of wars, of the rise and fall of nations, of the founding of cities, of the establishment of religions and theories, of the writing of books, of the invention of mechanisms, of the painting of pictures, of the carving of statues; in general, of the creative work that man has done.

The merely constructive man, unless he has been inventive also, has never constructed anything of a really novel kind. It is a matter of everyday experience that nearly all the things that are constructed are according to former patterns and the lessons of experience. All the constructive and engineering arts and sciences are studied and practiced for the purpose of enabling men to build bridges and houses and locomotives, etc., in such ways, as experience has shown to be good. Nearly all our acts, nearly all our utterances, nearly all our thoughts, are of stereotyped and conventional forms.

This condition of affairs possesses so many advantages that we cannot even imagine any other to exist. It enables a man to act nearly automatically in most of the situations of life. The main reason for drilling a soldier is that when confronted with the conditions of battle, he shall fire his musket and do his other acts automatically, undisturbed by the danger and excitement. Similarly, all our experience in life tends to automaticity. It is a very comfortable condition, for it demands the minimum amount of mental and nervous energy. The conductor demands your fare, and you pay it almost automatically. That a condition of automaticity prevails in nature, as we see it, one is tempted to suppose: for the seasons succeed each other with a regularity suggestive of it.

But even if the machine of nature and the machine of civilization are automatic now, we have no reason for believing that they always were so. Even the most perfect automatic engine had to be started at some time, and it had to be invented before it could be started; and it had also to go through a long process of development. Similarly, a man reads a paper almost automatically; but it required years of time to develop his ability to do so.

Now it has happened from time to time in history that some invention has broken in on the smoothly running machine of civilization and introduced a change. The gun did this, and so did the printing press. In every such case, a few men have welcomed the invention, but the majority have resented the change: some of them because their interests were threatened by it; others because of the instinctive but powerful influence of dislike of change.

The purely constructive man does not cause any such jolt. His work proceeds smoothly, uniformly, and usually with approval. But the inventive man, "his eye in a fine frenzy rolling," is visited with some vision which he cannot or will not dismiss, and which compels him to try to embody it in some form, and to continue to try until he succeeds in doing so, or gives up, confessing failure. The inventive man, having seen the vision, becomes a constructive man, and (in case he succeeds) puts the vision which he sees into such form that other people can see it also.

It is obvious therefore that two kinds of ability are needed to produce a really good invention of any kind, inventive ability and constructive ability; and it is also obvious that they are separate, though they cooperate. Many an invention of a quality that was mediocre or even inferior in originality, novelty and scope, has been quite acceptable by reason of the excellent constructive work that was done upon it: many a book and many an essay has succeeded almost wholly because of the skilful construction of the sentences; many a picture because of the accuracy of the perspective and the mixing of the colors; many a new mechanical device because of the excellent workmanship bestowed upon it. Conversely, many a grand and beautiful conception has failed of recognition because of the poor constructive work that was done on it. But occasionally a Shakespeare has given to the world an enduring masterpiece, the joint work of the highest order of invention and the highest order of constructive skill; occasionally a Raphael has painted a picture similarly conceived and executed; and occasionally an Edison has given the world a mechanical invention, comparably wonderful and perfect.

In all such cases, the start of the work was a picture on the mental retina; an image of something that was not, but might be made to be. A physical picture is actually made on the physical retina, but it cannot be recognized by the owner of the retina, unless a healthy optic nerve transmits it to his brain. Every mental picture must also be transmitted to the brain; and some mental pictures are very bright and clear. In some forms of insanity, the mental pictures are so clear that the patient cannot be persuaded that they are not physical; the patient sees a man approaching him, when there is no man approaching him; but the impression made on the patient's mind is the same as if there were.

The thought of the enormousness of the consequences that have followed the appearing of some visions to men (the vision of the gun, for instance) is almost stunning, if we try to realize the small area of the brain that the vision must have covered. If a line 1/4000 of an inch wide made on the physical retina and afterwards transmitted to the brain is seen with perfect clearness by the mind, what a small area of the brain must have been covered by the original vision of the gun! Yet how vast have been its consequences!

The fact that the inventor sees a vision, and then mentally arranges and rearranges the various material elements available in order to embody his vision in a painting, a project, a machine, a poem or a sonata, indicates that the essential processes of invention are wholly mental. This truth is illustrated by the work of every inventor, great or small. Possibly, the most convincing illustration is that given by the deaf Beethoven, who conceived and composed some of his grandest works when he could not physically hear a note.

Reference to the work of Roger Bacon has not been made, because of the doubts surrounding it.

CHAPTER VI
COLUMBUS, COPERNICUS, GALILEO AND OTHERS

Long before the Christian era the Chinese used pivoted magnetic needles to indicate absolute direction to them; but that they possessed or had invented the mariner's compass, there is considerable doubt. The history of the invention of the mariner's compass has not yet been written. It is not known when, or where, or by whom it was invented.

It is well-known, however, that the mariner's compass was in use in the Mediterranean Sea in the early part of the fifteenth century A. D. Guided by it, the navigators of that day pushed far out from land.

The first great navigational feat that followed the invention of the compass was that performed by the Portuguese, Bartholomew Dias, who conceived the idea of reaching India by going around Africa, and sailed down the west coast of Africa as far as its southern end, later called the Cape of Good Hope. It was a tremendous undertaking, and it had tremendous results; for it demonstrated the possibilities of great ocean voyages, proved that the road to India was very long, and led to the expedition of Columbus, six years later. It was also a great invention, both in brilliancy of conception and excellence of execution, although Dias did not reach India.

The second great navigational feat was performed by Christopher Columbus in 1492. Before that time it was conceded by most men of learning and reflection that the earth was spherical; and it was realized that, if it was spherical, it might be possible by sailing to the westward to reach India, the goal of all commercial expeditions in that day. Columbus is not to be credited with the first conception of that possibility.

But that conception rested undeveloped in the minds of only a few men. Had it not been for Columbus, or some man like him, it would have remained undeveloped and borne no fruit. The Savior in his parable tells us of the sower who went forth to sow, and tells us also that most of the grain fell on stony ground. So it is with most of the opportunities that are offered to us every day; and so it is even with most of the visions that are placed before our minds. But the Savior tells us also of other grains that fell on good ground and bore abundant fruit. Such are the conceptions that the great inventors have embodied; such was the conception that fell on the good ground of the mind of Christopher Columbus.

The conception that came to him was not of the possibility that someone could sail west and eventually reach India, but of preparing a suitable expedition himself and actually sailing west and reaching India. The conception must have been wonderfully powerful and clear, for it dominated all his life thereafter. But he could not make others see the vision that he saw. For many years he went from place to place, trying to get the means wherewith to prepare his expedition. He made only a few converts, but he did make a few. Some of these exerted their influence on Queen Isabella of Spain. She, together with her husband Ferdinand, then supplied the money and other necessaries for the expedition.

The invention of the gun was followed by the invention of printing in 1434, and this by the discovery of America in 1492. These three epochal occurrences started the new civilization with a tremendous impetus. This impetus was immediately reinforced by the voyage of the Portuguese Admiral, Vasco da Gama, around the Cape of Good Hope to India in 1497–1498, and the circumnavigation of the globe by Ferdinand Magellan in 1519–1522.

The immediate practical influence of da Gama's feat was almost to kill the commerce of the cities of Italy and Alexandria with India by way of the Red Sea and the Indian Ocean, and to transfer the center of the sea-commerce of the world to the west coast of Europe, especially Portugal. Near the west coast it has rested ever since; though but little of it stayed long with Portugal.

While Magellan's voyage was not quite so important as the discovery of America, it was not immeasurably less so; for it set at rest forever the most important question in geography,—was the earth round or not? The voyage of Columbus had not answered it, because he returned by the same route as that by which he went. But Magellan started in a southwesterly course, and one of his ships again reached home, coming from the east. The Victoria had circumnavigated the globe! Only eighteen men and one ship returned. The other ships and the other men had perished. Magellan himself had been buried in the Philippines.

The news of Magellan's great exploit and the stories that came to Europe of the riches beyond the sea, resulted soon in an idea coming to the mind of Hernando Cortez, the development of that idea into a concrete plan, and the making of a complete invention. This was a plan by which he should head an expedition to a certain part of the New World, and "convert" the heathen dwelling there; doing whatever killing and impoverishing and general maltreatment might be found to be convenient or desirable. The invention worked perfectly; some half-savage Indians of what we now call Mexico were "converted," many were killed, and untold treasure was forcibly obtained.

The success of this invention was so great that Francisco Pizarro was inspired to copy it, and to try it on some Indians in a country that now we call Peru. Whether Pizarro improved on Cortez's scheme, or whether the conditions of success were better need not concern us now: the main fact seems to be that Pizarro was able to convert and kill and impoverish and generally ruin more effectively than Cortez.

Following Cortez and Pizarro, many expeditions sailed from Spain to the West Indies, Central America and South America, and carried out similar programs. The two principal results were that those parts of the world were soon dominated by Spain, and that the people of Spain received large amounts of gold and treasure. The main result to them was that they succumbed under the enervating influence of the artificial prosperity produced, and rapidly deteriorated. By the end of the hundred years' period after Columbus discovered America, Spain was clearly following the downward path, and at high speed.

One of the early results of the invention of printing was an increased ability of people separated by considerable distances to interchange their views; and a still greater though allied result was an increased ability of men of thought and courage to impress their thoughts upon great numbers of people. At the time when printing was invented, the Church of Rome had ceased to dominate European nations as wholly as it had done before; but it exercised a vast power in each country. This was because of its prestige, its hold on the clergy and the Church property, and its authority in many questions connected with marriage, wills, appointments, etc. This was resented, but impotently, by the various sovereigns.

It was realized also (and it came to be realized with increasing clearness toward the end of the fifteenth century) that there were many grave evils and scandals in the Church, even in the highest quarters. The printing-press lent itself admirably to the dissemination of views on this matter: so that there gradually grew up a strong and widespread feeling of discontent. But despite considerable friction as to the limits of their respective functions, the Church and the State were so intimately allied in every country, and each realized so clearly its dependence on the other, that no movement of any magnitude against even the acknowledged evils had been able to gain ground. No man appeared who was able to conceive and execute a plan that could successfully effect reform.

But such a man appeared in the year 1517, whose name was Martin Luther. He was a poor monk; but a knowledge of virtually all there was to know lived in his mind, coupled with imagination to conceive, constructiveness to plan, and courage to perform. In that fateful year, 1517, the Pope sent agents through the world to sell "indulgences," which remitted certain temporal punishments for sin, in return for gifts of money. The agent who was commissioned for Germany carried out his work with so little tact and moderation, that he made the granting of indulgences seem even a more scandalous procedure than it really was. Luther had been preaching the doctrine of a simple following of the teachings of the Savior, and deprecating a too close adherence to mere forms and ritual. He now seems to have conceived a clean-cut plan of effective action; for on the evening before the indulgences were to be offered on All Saints Day, in the Church of Wittemberg, Luther nails on the door his celebrated ninety-five theses against the sale. The printing-press reproduced copies of these in great numbers throughout Germany. A definite sentiment antagonistic to the indulgences developed rapidly, and a general movement toward the reform of the abuses in the Church took shape. Luther was threatened with excommunication by the Pope in 1520, but he burned a copy of the "papal bull" in a public place on December 10 of that year.

The emperor of Germany convened a meeting of the Diet at Worms in 1521, at which he exerted all his powers to make Luther retract: but in vain. So great a following did Luther now have that, though the emperor put him under ban, and all persons were forbidden to feed or give him shelter, he was cared for secretly by men in high position, until he voluntarily came out of hiding, and appeared in Wittemberg. The emperor called a meeting of the Diet at Spires in 1526, and another meeting in 1529. Both meetings had for their object the suppression of the movement begun by Luther. It was against a decree made by the second Diet that certain high officials and others made the famous protest, that caused the name to be affixed to them of Protestants. This name has been perpetuated to this day.

As is well known, the movement resulted, after nearly a hundred years of disturbed conditions, in a series of wars, called "The Thirty Years' War" that began in 1618, and ended with the Peace of Westphalia in 1648. This Peace marked the end of the Reformation period, and resulted in establishing Protestantism in North Germany, Denmark, Norway, Sweden, England and Scotland.

The influence of Luther's conception with its subsequent development was thus definite, widespread and profound, even if regarded from a merely religious point of view: but the influence it had on religion was only a part of its total influence. In words, the protest was against certain abuses in the Roman Church; but in fact it was against a domination exercised over the minds and souls of men. Luther's influence was in reforming not only the Roman Catholic Church and the practice of the Christian religion throughout Europe, but also the conditions under which men were allowed to use their minds.

While the inventions in mechanism, religion, etc., which we have just noted were going on during the fifteenth and sixteenth centuries, others were going on in the realm of science. The movement was begun about 1507 by a young man named Nicolas Copernicus, who was executing the dissimilar functions of canon, physician and mathematician in the little town of Frauenberg in Poland. Copernicus at this time was thirty-four years old, but he had even then devoted the major activities of his mind to astronomy for several years. Naturally, his efforts had been devoted to mastering whatever of the science then existed. The efforts of most people in dealing with any subject end when they have gone thus far—and very few go even thus far. But Copernicus noted that, while the Ptolemaic System (suggested, though probably not invented by the Egyptian king) was the one generally accepted, it did not account for many of the phenomena observed; that none of the other systems that had been suggested afterward explained matters more satisfactorily, and that no one of the systems was in harmony with any other.

Thereupon this daring young man conceives the idea of inventing a system of astronomy himself, in which all the movements of the heavenly bodies should be shown to be in accordance with a simple and harmonious law. Seizing on this idea, he proceeds at once to develop it; and he works on it until death takes him from his labors in 1543 at the age of seventy.

The whole civilized world had virtually accepted the Ptolemaic Theory,—at least, the part of it which assumed that the earth was the center of the universe, the sun and stars and planets revolving around it. Copernicus invented the theory that the sun was the center, that the earth and the other planets revolved around it, and that the earth revolved on its own axis once in twenty-four hours. So great was the insistence of the religious bodies in adhering to the Ptolemaic Theory, so set were the minds of all men of high position on it, that though Copernicus wrote a book expounding his own theory, he did not think it wise to publish it. He seems to have completed the book in about 1530. He did not publish it till 1543. Just before its printing was finished, Copernicus was taken ill. The first volume was held before him. He touched it and seemed to realize dimly what it was. Then he relapsed into torpor almost immediately, and soon died.

It is interesting to note that Copernicus was not the first to conceive the idea that the earth turns on its own axis, or that the earth revolves around the sun, any more than Bell was the first to conceive the idea that speech could be transmitted by a suitable arrangement of magnet, diaphragm and electric circuit. But Copernicus was the first to invent a system of astronomy that was like a machine. It was a usable thing. It could be made to explain astronomical phenomena and predict astronomical events correctly.

It may be well to remind ourselves again that no application for patent will be granted by our Patent Office unless the invention is described and illustrated so clearly and correctly that "a person skilled in the art can make and use it;" and to realize that this admirable phraseology may be utilized to distinguish any other novel endeavor of man entitled to be called an invention from any other not so entitled; for no system, no theory, no religion, no scheme of government, regardless of how attractive it may be, is entitled to be called an invention, unless, like the Copernican System, "a person skilled in the art can make and use it."

Shortly after Copernicus, came Johann Kepler, who was born in Württemburg in 1571, and died in 1630. He had been a pupil of Tycho Brahe, who did not succeed in making any great invention or discovery, but who did collect a great amount of data. Utilizing these, Kepler devoted many years to the study of Copernicus, and tried to invent a system which would explain some facts of astronomy that the system of Copernicus did not explain, notably the non-uniform speed of the planets. The main result of his labors was the famous Kepler's Laws, which were

"1. The orbits of the planets are ellipses having the sun at one focus.

"2. The area swept over per hour by the radius joining sun and planet is the same in all parts of the planet's orbit.

"3. The squares of the periodic times of the planets are proportional to the cubes of their mean distances from the sun."

These three discoveries, enunciated in three interdependent, concrete laws, constituted an invention which, while it was merely an improvement on Copernicus's, was so great an improvement as almost to make the difference between impracticability and practicability. Without this improvement, astronomy would not be what it is, navigation would not be what it is, the regulation of time throughout the world would not be what it is, and the present highly intricate but smoothly running machine of civilization could not exist at all, except in a vastly inferior form. The machine of civilization is dependent for its successful operation on the good quality and correct design of every other part. So is every other machine; for instance, a steam-engine.

The Copernican System was not recognized for more than a century. It was, in fact, definitely rejected, and people were subjected to punishment and even torture for declaring their belief in it.

One of the amazing facts surrounding Copernicus's invention was that he carried on his observations with exceedingly crude appliances. The telescope had not yet been invented.

Who invented the telescope is not definitely known; but it is probable that both the telescope and the microscope (compound microscope) were invented by Jansen, a humble spectacle-maker in Holland. Both inventions were made about the year 1590, and were of the highest order of merit from the three main points of view,—originality, completeness and usefulness. Few inventions more perfectly possessing the attributes of a great invention can be specified. The originality of the conception of each seems unquestionable; the beautiful completeness of the embodied form of each was such that only improvements in detail were needed afterward; and, as to their usefulness, can we even imagine modern civilization without them both?

The interesting fact may now be called to mind that, although many men who lived in Jansen's time were loaded with honors and fame and wealth and glory, the inventor of the telescope and the microscope received no reward of any kind that we know of; and his fame has come to us so imperfectly that we are not even sure that Jansen was his name.

The man usually credited with the invention of the telescope is Galileo, though Galileo himself never pretended that he invented it, and though historical statements are clear that he heard that such an instrument had been invented, and then designed and constructed one himself in a day. It would be interesting to know just how much information Galileo received. It seems that his information was very vague. If so, a considerable amount of inventiveness may have been required, besides a high order of constructiveness. But the mere fact that Galileo knew that such an instrument had been invented caused his mental processes to start from an image put into his mind by an outside agency and not from his own imagination. Galileo's work did not begin with conception, and therefore it was not an invention.

Galileo was one of the foremost and most ardent supporters of the Copernican Theory; and it was on his skilful and industrious use of the telescope in making observations confirming the theory that his fame mainly rests. As late as 1632, nearly a century after Copernicus's doctrine had become known, Galileo was compelled by threat of torture to recant, and was condemned to imprisonment for life.

The influence of inventions on history has been greater and more beneficial than that of any other single endeavor of man. Yet most inventions have been resisted. The invention of Copernicus was resisted for more than a century by the organization commanding the greatest talent and character and learning that the world contained.

The extraordinary access of mental energy in Europe about the beginning of the seventeenth century is illustrated by another invention virtually contemporaneous with those of Copernicus and Jansen, and also in the line of mathematical research. This was the invention by Baron John Napier of logarithms.

It was a curious invention—an invention the like of which one cannot easily specify; for the thing invented was not a material mechanism, or a theory, or anything exactly like anything else. It is difficult to classify a logarithm except as a logarithm:—yet Napier did create something; he did make something exist that had not existed before; he did conceive an idea and embody that idea in a concrete machine. That machine, in the hands of a man who understood it, could supply extraordinary assistance in making mathematical calculations, especially calculations involving many operations and many figures, as in astronomy. It has been in continual use since Napier invented it, and is used still. In order to indicate the simplicity and the value of Napier's invention, it may assist those who have forgotten what a logarithm is, or who have been so fortunate as never to have been compelled to study about them, to state that logarithms are numbers so adapted to numbers to be multiplied, divided, or raised to any power, that one simply adds their logarithm, subtracts one logarithm from the other or multiplies or divides a logarithm by the number representing the power, and then notes in a table the number resulting, instead of going through the long process of multiplying, dividing, squaring, etc. Of course, in the case of small numbers, the use of logarithms is not only unnecessary but undesirable; but in the case of the long numbers used in astronomy, and even in navigation, logarithms are inexpressibly helpful and time-saving. The mental feat of Napier consisted in conceiving the idea of accomplishing what he subsequently did accomplish, and then constructing and producing the "logarithmic tables" that made it possible.

Another indication of the new intellectual movement in Europe was the experiments, deductions and inventions of William Gilbert, an English physician, who lived from 1540 till 1603. According to the use of the word invention followed in this book, only two actual inventions can be credited to Gilbert, that of the electroscope and that of magnetization. Gilbert's work was valuable in the highest degree, more valuable than that of most inventors; and yet it was more inductive and deductive than inventional. It is not the purpose of this book to suggest that invention has been the only kind of work that men have done which has had an influence on history; and the work of Gilbert gives the author an opportunity to emphasize the value of certain work which is not inventional. At the same time, the author cannot resist the temptation of pointing out that Gilbert's work was original and constructive, that it hovered around the borders of invention, and that it did more to assist the inventors of the electric and electro-magnetic appliances that were soon to follow, than the work of almost any other one man.

The full influence of Gilbert's work was not apparent for many years; not, in fact, until the discoveries and inventions of Volta, Galvani and Faraday showed the possibilities of utilizing electricity for practical purposes. Then the facts which Gilbert had established, and the discoveries built upon them afterward, were the basis of much of the work of those great men, and of the vast science of electrical engineering that resulted.

The inventions made before the opening of the seventeenth century A. D., wonderful as they were, were quite widely separated in time, and seem to have been wholly the outcome of individual genius, and not the result or the indication of any widespread intellectual movement. But soon after it opened, the influence of printing in spreading knowledge became increasingly felt, and inventions began to succeed each other with rapidity, and to appear in places far apart.

In the beginning of the seventeenth century, certain writings appeared in England that took great hold on the minds of thinking men, not only in England, but throughout Europe. The name of the author was Francis Bacon.

It would not be within the scope of this book even to attempt to analyze the philosophy of Bacon, to differentiate between it and the philosophy of Aristotle or any other of the great thinkers of the world, or to try to trace directly the influence of Bacon's philosophy on his own time and on future times. It is obvious, however, that Bacon invented a system of inductive reasoning that assisted enormously to give precision to the thoughts of men in his own day, by convincing them of the necessity of first ascertaining exact facts, and then inferring correct conclusions from those facts. This seems to us an easy thing to do, looking at the matter in the light of our civilization. But it was not easy, though Bacon's high position gave him a prestige exceptional for a philosopher to possess; and this smoothed his way considerably. Men had not yet learned to think exactly. The efforts of even the great minds were of a groping character; and fanciful pictures made by the imagination seem to have intertwined themselves with facts, in such a way that correct inferences (except in mathematical operations) were hardly to be expected. Bacon insisted that every start on an intellectual expedition should be made from absolutely indisputable facts.

The first effect of such teaching was to make men seek for facts. Not long afterward, we find that many men were making it the main business of their lives to seek for facts from Nature herself. This does not mean that men had not sought for facts before from Nature, or that Bacon alone is to be credited with the wonderful increase in the work of research and investigation that soon began.

Bacon's principal book was published in 1620, and called the "Novum Organum," or "the new instrument." It was obviously an invention, for it was a definite creation of a wholly new thing, that originated in a definite conception, and was developed into a concrete instrument. That Bacon so regarded it is evident from the title that he gave it. Furthermore, he described it as "the science of a better and more perfect use of reason in the investigation of things and of the true aids of the understanding." Bacon was a patient of Dr. Harvey, who discovered the circulation of the blood; and it would be strange indeed if Bacon's philosophy did not give to Harvey a great deal of guidance and suggestion that furthered his experiments.

William Harvey discovered the fact that the blood circulates in the bodies of living animals. This declaration stated by itself would convey to the minds of some the idea that Harvey discovered it, somewhat as a boy might discover a penny lying on the ground. The first definition of the word discover in the Standard Dictionary is "to get first sight or knowledge of"; so that the mere announcement that an investigator has "discovered" something gives to many people an incorrect idea of his achievement. Harvey discovered the fact of the circulation of the blood after years of experimentation and research on living animals, and by work of a most laborious kind. His conclusions were not accepted by many for a very considerable period; but he was fortunate, like Bacon, in holding a position of such influence and prestige, that he escaped most of the violent opposition that inventors usually meet.

Harvey's discovery did not of itself constitute an invention; but the embodiment of that discovery in a concrete theory, so explained "that persons skilled in the art could make and use it," did constitute an invention of the most definite kind. The whole influence of that invention on history, only a highly equipped physician could describe; but, nevertheless, one may feel amply justified in stating that its influence on the science and practice of surgery and medicine, and on the resulting health of all the civilized nations of the world, has been so great as to be incalculable.

A contemporary and acquaintance of Harvey was Robert Boyle, one of the most important of the early scientific investigators, who was an avowed disciple of Bacon, and followed his methods with conscientious care. His work covered a large field, but it was concerned mostly with the action of gases. He is best known by "Boyle's Law," which is usually expressed as follows: "When the volume of a mass of gas is changed, keeping the temperature constant, the pressure varies inversely as the volume; or the product of the pressure by the volume remains constant." While it has been found that this law is not absolutely true with all gases at all temperatures and pressures, its departure from accuracy are very small, and these are now definitely known. With certain tabulated corrections, this law is the basis on which most of the calculations for steam engines, air engines and gas engines are made. It is usually expressed by the formula

p v = p´ v´ = constant.

Boyle is said to have "discovered" this law, and Harvey is said to have "discovered" the circulation of the blood. Doubtless they did: but if they had done no more than "discover" these things, no one else would have been the wiser, and the world would have been no richer. What these two men did that made us wiser and the world richer, was to make inventions of definite character, and give them to the world in such manageable forms, that "persons skilled in the art can make and use them."

In 1620, the spirit thermometer, as we know it now, was invented by Drebel. It is by some ascribed to Galileo. An interesting controversy has been waged as to which was actually the inventor. The facts seem to be that Galileo did invent a thermometer in which the height of water in a glass tube indicated approximately the temperature. The tube was long and ended in a bulb at the top. The bulb being warmed with the hand of Galileo, and the open lower end of the tube being immersed in water, and then the warmth of the hand removed, water rose in the tube to a height depending on the warmth of the air in the bulb. The height of the water therefore varied inversely as the temperature. The defect of the instrument was that it was a barometer as much as it was a thermometer; because the varying pressure of the atmosphere caused the water to rise and fall accordingly, and thus falsify the thermal indications. Drebel realized this, and closed both ends of the tube.

Thus Galileo came very near to inventing both the thermometer and the barometer, but yet invented neither! It seems incredible that he should have failed to invent the barometer, having come so near it; for he had been engaged for a long period in investigating the weight of air, and finally had succeeded in ascertaining it. The barometer was invented or rather discovered by Galileo's successor, Torricelli, in 1645. Torricelli, in investigating the action of suction pumps, constructed what now we call a barometer; but it was not until after he had constructed it that he realized that the height of mercury in his tube indicated the pressure of the air outside. Seventy-five years later, Fahrenheit made a great improvement in the thermometer by substituting mercury for spirits.

Meanwhile, Otto von Guericke, following in the footsteps of Galileo and Torricelli, had invented the air-pump, by means of which he succeeded in getting a fairly perfect vacuum in a glass receiver. This seems to have been an invention of the most clear-cut kind, resulting from an idea that occurred to Guericke that he seized upon promptly and put to work to serve mankind. Its influence in giving impetus to the science and art of pneumatics, and the influence of pneumatics on the progress of civilization, are too obvious to need more than to be pointed out. The invention of Guericke is a simple and clear illustration of the "power of an idea"; an illustration of seed falling on good ground and bringing forth fruit an hundred fold.

One of the greatest inventors that ever lived was Isaac Newton, who lived from 1642 till 1728. Even as a child he busied himself with contriving and constructing mechanical appliances, mostly toys. As a young man he occupied himself mostly with studies in mathematics and experiments in physics, especially optics. In 1671 he invented a special form of the reflecting telescope, called after him the Newtonian telescope. He made many experiments in optics, in consequence of which he discovered and announced that white light consists of seven colors, having different degrees of refrangibility. The influence of this discovery on the advancement of learning since that time, it is unnecessary to point out; but we cannot realize too clearly that without it much of the most important progress in optics since that time would have been impossible.

The invention by reason of which Newton is most generally known is his theory or law of gravitation, which he announced in his Principia, published in 1686. In 1609, Kepler had announced his famous laws, that reads:

"1. The orbits of planets are ellipses having the sun at one focus.

"2. The area swept over per hour by the radius joining sun and planet is the same in all parts of the planet's orbit.

"3. The squares of the periodic times of the planets are proportional to the cubes of their mean distances from the sun."

Newton showed from the laws of mechanics which he had discovered that, assuming the first two laws of Kepler to be true, each planet must always be subject to a force directing it toward the sun, that varies inversely as the square of its distance from the sun: otherwise, it would fly away from the sun or toward it. From this, Newton inferred that all masses, great and small, attract each other with a force proportional to their masses, and inversely proportional to the square of the distance between them, and invented what is now called the law of universal gravitation.

Another invention of possibly equal value, also published in his Principia, but not so generally known, is his three laws of motion. These are

"1. Every body continues in its state of rest, or of moving with constant velocity in a straight line, unless acted upon by some external force.

"2. Change of momentum is proportional to the force and to the time during which it acts, and is in the same direction as the force.

"3. To every action there is an equal and contrary re-action."

It is probably impossible for any human mind to conceive any invention of a higher order of originality than either of these two, or to construct any invention more concrete and useful. Certainly no more brilliant inventions have ever yet been made. These two wonderful products of Newton's genius underlie the whole structure of modern astronomy and modern mechanics. The sciences of modern astronomy and modern mechanics could not exist without them, and would not now exist unless Newton (or someone else) had invented them.

It may be pointed out that Newton's conception of our solar system is that of a machine in rapid motion, of which the sun and the planets are the principal parts.

Another important invention ascribed to Newton is that of the sextant, a small and easily handled instrument, used ever since in ships for purposes of navigation; but whether he should receive the entire credit for this invention seems quite doubtful; for another astronomer, Robert Hooke, is credited by some with the original suggestion, and John Hadley, still another astronomer, with having adapted it to practical sea use. Numerous other scientific inventions, however, that have formed the basis of much of the scientific work of later experimenters and inventors are clearly to be credited to Newton. Among these, his formula for the velocity of a wave of compression, his color-wheel, and his simple apparatus known as "Newton's rings," by which can be measured the wave lengths of light of different colors, are possibly the most important.

In approximate coincidence with the Renaissance movement and the accompanying awakening of the intellect of Europe, there began a conflict between the sovereigns and the Pope. The Popes had gradually acquired great power, because of their prestige as the successors of St. Peter, to whom it was declared our Savior had given the keys of heaven. Coincidentally, the multitudinous barons had gradually built up the Feudal System. This was a loose-jointed contrivance, under which Europe was virtually divided into little geographical sections, ruled over by hereditary feudal lords, who in each country owed allegiance to a sovereign. By reason of the slowness and uncertainty of transportation and communication, the various feudal lords were extremely independent, and each one did substantially as he willed in his little domain.

The situation was a miserable one for every person, except the Pope, the sovereigns, the feudal lords and their hangers-on; not only because of the various petty tyrannies, but because of the continual little wars and the general absence of good government. Gradually, the sovereigns got more and more power (except in England) and the conditions improved so much that the people realized that it was better to be ruled by one king, or emperor, than by a multitude of barons. The sovereigns finally acquired so much power that they dared to oppose the Pope in many of his aggressions; but no very important situations were developed until the Reformation caused the existence of protestant or heretic sovereigns, and the occasional excommunication of one of them by the Pope, with its attendant exhortation to his subjects to take up arms against him. To meet this situation, the theory of the Divine Right of Kings was invented.

This was a very important invention; for it offset the Divine authority of the Pope as Pope, and gave a theme for the bishops and priests in their discourses to the people, and a slogan for the soldiers. It was extremely successful for three centuries, and its influence was in the main beneficent. It worked for the establishment of stable governments and great nations, tended to prevent the excessive domination of a religious organization, and, by recognizing the fact that every sovereign's power comes from the Almighty, it suggested the sovereign's responsibility to Him. At first this suggestion evidently bore little fruit; for the seventeenth and eighteenth centuries were characterized by general oppression of the people, and filled with dynastic wars, waged merely in behalf of monarchical ambitions. But gradually the kings and the peoples came to realize the duties of sovereigns, as well as their privileges and powers. Gradually then, the view came to be held that kings were bound to exercise their power for the benefit of their people.

Even the doctrine of the Divine Right of Kings, now condemned and obsolete, had a great influence and a good influence during the time it was in vogue; and it supplies a clear illustration of the power of a good idea, skillfully developed, to fulfill a given purpose, so long as its existence is necessary.

Most men have a considerable amount of energy, but do not know what to do with it. Children are in the same category, except that toys have been invented for them, and parents give these toys to their children. Without toys, children find the days very long, and parents find their children very trying. The usefulness of toys seems to be mainly, not so much in giving children pleasure directly, as in supplying an outlet for their energies, both physical and mental. For what greater pleasure is there than in expending one's natural energies under pleasant conditions?

Possibly, all the work that men have done in building up civilization is like the work that children have done with building blocks. Certainly there are many points of similarity. The mental efforts are similar; and, so far as we can see, the results are similar also. Toy temples have been built of building blocks, and then have been destroyed. Civilizations also have been built and then destroyed. And in the case of both the building blocks and the civilizations, the pleasure seems to come, not from the result achieved, but from an enjoyable expenditure of energy in achieving it. In both cases it has been the inventors who have pointed out the ways in which to expend the energy, and achieve the results.

CHAPTER VII
THE RISE OF ELECTRICITY, STEAM AND CHEMISTRY

The invention of the first electrical machine was made by Otto Von Guericke, of Magdeburg, about 1670. It consisted of a sulphur ball, a stick with a point, and a linen thread "an ell or more long," hanging from the stick. The lower end of the thread being made to hang "a thumb breadth distance" from some other body, and the sulphur ball rubbed and brought near the point of the stick, the lower end of the thread moved up to the body. The ball being removed, the lower end of the thread would drop away from the body; so that by moving the ball back and forth, the lower end of the thread would be made to move back and forth simultaneously.

It may be objected that Guericke made no invention, because he did not conceive the idea of making a machine or instrument and did not, in fact, produce one: that he merely made a discovery. The author admits that such an objection would have great reasonableness, and that Guericke's feat is a little hard to class. It is classed by many as an invention, however, and the present author is inclined to class it so; because there seems no reason to doubt that Guericke first conceived the idea of doing what he did do, and that he did produce a device whereby an actual motion of a rubbed ball at one place caused actual motion at another place, through the medium of a current of electricity that traversed a conductor joining the two places. The device is sometimes spoken of as the first telegraph instrument.

Guericke (like Gilbert) was more distinctly an experimenter than an inventor,—and (like Gilbert) his work was not only in electricity, but in most of the other branches of science. Of the two, Guericke seems to have covered a wider field, and to have been more distinctly an inventor. His celebrated experiment of holding two hollow hemispheres together, then exhausting the air from the hollow sphere thus formed, and then demonstrating the force of the atmosphere by showing that sixteen horses could not pull the hemispheres apart, indicates just the kind of clear apprehension of the laws of Nature that characterizes the inventor.

By some, Guericke is esteemed the inventor of the first electric light, because by rubbing a sulphur ball in a dark room he produced a feeble electric illumination. Of Guericke's discoveries and inventions, the only one that has survived as a concrete apparatus is the air pump; but it is doubtful if the direct influence on history of the air pump, great as it has been, has actually been any greater than the indirect influence of his less widely known discoveries and experiments.