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THE STORY OF STEAM.

What Steam is.--Steam in Nature.--The Engine in its earlier forms.--Gradual explosion.--The Hero engine.--The Temple-door machine.--Ideas of the Middle Ages.--Beginnings of the modern engine.--Branca's engine.--Savery's engine.--The Papin engine using cylinder and piston.--Watt's improvements upon the Newcomen idea.--The crank movement.--The first use of steam expansively.--The "Governor."--First engine by an American Inventor.--Its effect upon progress in the United States.--Simplicity and cheapness of the modern engine.--Actual construction of the modern engine.--Valves, piston, etc., with diagrams.

THE AGE OF STEEL.

The various "Ages" in civilization.--Ancient knowledge of the metals.--The invention and use of Bronze.--What Steel is.--The "Lost Arts."--Metallurgy and chemistry.--Oriental Steel.--Modern definition of Steel.--Invention of Cast Steel.--First iron-ore discoveries in America.--First American Iron-works.--Early methods without steam.--First American casting.--Effect of iron industry upon independence.--Water-power.--The trip-hammer.--The steam-hammer of Nasmyth.--Machine-tools and their effects.--First rolling-mill.--Product of the iron industry in 1840-50.--The modern nail, and how it came.--Effect of iron upon architecture.--The "Sky-Scraper."--Gas as fuel in iron manufactures.--The Steel of the present.--The invention of Kelley.--The Bessemer process.--The "Converter."--Present product of Steel.--The Steel-mill.

THE STORY OF ELECTRICITY.

The oldest and the youngest of the sciences.--Origin of the name.--Ancient ideas of Electricity.--Later experiments.--Crude notions and wrong conclusions.--First Electric Machine.--Frictional Electricity.--The Leyden Jar.--Extreme ideas and Fakerism.--Franklin, his new ideas and their reception.--Franklin's Kite.--The Man Franklin.--Experiments after Franklin, leading to our present modern uses.--Galvani and his discovery.--Volta, and the first "Battery."--How a battery acts.--The laws of Electricity, and how they were discovered.--Induction, and its discoverer.--The line at which modern Electricity begins.--Magnetism and Electricity.--The Electro-Magnet.--The Molecular theory.--Faraday, and his Law of Magnetic Force.

MODERN ELECTRICITY.

THE STORY OF STEAM

That which was utterly unknown to the most splendid civilizations of the past is in our time the chief power of civilization, daily engaged in making that history of a new era that is yet to be written in words. It has been demonstrated long since that men's lives are to be influenced not by theory, or belief, or argument and reason, so much as by that course of daily life which is not attempted to be governed by argument and reason, but by great physical facts like steam, electricity and machinery in their present applications.

The greatest of these facts of the present civilization are expressed in the phrase, Steam and Steel. The theme is stupendous. Only the most prominent of its facts can be given in small space, and those only in outline. The subject is also old, yet to every boy it must be told again, and the most ordinary intelligence must have some desire to know the secrets, if such they are, of that which is unquestionably the greatest force that ever yielded to the audacity of humanity. It is now of little avail to know that all the records that men revere, all the great epics of the world, were written in the absence of the characteristic forces of modern life. A thousand generations had lived and died, an immense volume of history had been enacted, the heroes of all the ages, and almost those of our own time, had fulfilled their destinies and passed away, before it came about that a mere physical fact should fill a larger place in our lives than all examples, and that the evanescent vapor which we call steam should change daily, and effectively, the courses and modes of human action, and erect life upon another plane.

It may seem not a little absurd to inquire now "what is steam?" Everybody knows the answer. The non-technical reader knows that it is that vapor which, for instance, pervades the kitchen, which issues from every cooking vessel and waste-pipe, and is always white and visible, and moist and warm. We may best understand an answer to the question, perhaps, by remembering that steam is one of the three natural conditions of water: ice, fluid water, and steam. One or the other of these conditions always exists, and always under two others: pressure and heat. When the air around water reaches the temperature of thirty-two degrees by the scale of Fahrenheit, or ? or zero by the Centigrade scale, and is exposed to this temperature for a time, it becomes ice. At two hundred and twelve degrees Fahrenheit it becomes steam. Between these two temperatures it is water. But the change to steam which is so rapid and visible at the temperature above mentioned is taking place slowly all the time when water, in any situation, is exposed to the air. As the temperature rises the change becomes more rapid. The steam-making of the arts is merely that of all nature, hastened artificially and intentionally.

The element of pressure, mentioned above, enters into the proposition because water boils at a lower temperature, with less heat, when the weight of the atmosphere is less than normal, as it is at great elevations, and on days when, as we now express it, there is a low barometer. Long before any cook could explain the fact it was known that the water boiling quickly was a sign of storm. It has often been found by camping-parties on mountains that in an attempt to boil potatoes in a pot the water would all "boil away," and leave the vegetables uncooked. The heat required to evaporate it at the elevation was less than that required to cook in boiling water. It is one of the instances where the problems of nature intrude themselves prominently into the affairs of common life without previous notice.

This universal evaporation, under varying circumstances, is probably the most important agency in nature, and the most continuous and potent. There was only so much water to begin with. There will never be any less or any more. The saltness of the sea never varies, because the loss by evaporation and the new supply through condensation of the steam--rain--necessarily remain balanced by law forever. The surface of our world is water in the proportion of three to one. The extent of nature's steam-making, silent, and mostly invisible, is immeasurable and remains an undetermined quantity. The three forms of water combine and work together as though through intentional partnership, and have, thus combined, already changed the entire land surface of the world from what it was to what it is, and working ceaselessly through endless cycles will change it yet more. The exhalations that are steam become the water in a rock-cleft. It changes to ice with a force almost beyond measurement in the orderly arrangement of its crystals in compliance with an immutable law for such arrangement, and rends the rock. The process goes on. There is no high mountain in any land where water will not freeze. The water of rain and snow carries away the powdered remains from year to year, and from age to age. The comminuted ruins of mountains have made the plains and filled up and choked the mouth of the Mississippi. The soil that once lay hundreds of miles away has made the delta of every river that flows into the sea. The endless and resistless process goes on without ceasing, a force that is never expended, and but once interrupted within the knowledge of men, then covered a large area of the world with a sea of ice that buried for ages every living thing.

The common idea of the steam that we make by boiling water is that it is all water, composed of that and nothing else, and this conception is gathered from apparent fact. Yet it is not entirely true. Steam is an invisible vapor in every boiler, and does not become what we know by sight as steam until it has become partly cooled. As actual steam uncooled, it is a gas, obeying all the laws of the permanent gases. The creature of temperature and pressure, it changes from this gaseous form when their conditions are removed, and in the change becomes visible to us. Its elasticity, its power of yielding to compression, are enormous, and it gives back this elasticity of compression with almost inconceivable readiness and swiftness. To the eye, in watching the gliding and noiseless movements of one of the great modern engines, the power of which one has only a vague and inadequate conception seems not only inexplicable, but gentle. The ponderous iron pieces seem to weigh nothing. There is a feeling that one might hinder the movement as he would that of a watch. There is an inability to realize the fact that one of the mightiest forces of nature is there embodied in an easy, gliding, noiseless impulse. Yet it is one that would push aside massy tons of dead weight, that would almost unimpeded crush a hole through the enclosing wall, that whirls upon the rails the drivers of a locomotive weighing sixty tons as though there were no weight above them, no bite upon the rails. There is an enormous concentration of force somewhere; of a force which perhaps no man can fairly estimate; and it is under the thin shell we call a boiler. Were it not elastic it could not be so imprisoned, and when it rebels, when this thin shell is torn like paper, there is a havoc by which we may at last inadequately measure the power of steam.

Hero appears to the popular imagination as the greatest inventor of the past. Every school boy knows him. Archimedes, the Greek, was the greater, and a hundred and fifty years the earlier, and was the author of the significance of the word "Eureka," as we use it now. But Hero was the pioneer in steam. He made the first steam-engine, and is immortal through a toy.

And when experiments at last began to be made in the mechanisms by which steam might be utilized they were such as boys now make for amusement; such as throwing a steam-jet against the vanes of a paddle-wheel. Such was Branca's engine, made nine years after the landing of our forefathers at Plymouth, and thought worthy of a description and record. The next attempt was much more practical, but cannot be accurately assigned. It consisted of two chambers, from each of which alternately water was forced by steam, and which were filled again by cooling off and the forming of a vacuum where the steam had been. One chamber worked while the other cooled. It was an immense advance in the direction of utility.

About 1698, we begin to encounter the names that are familiar to us in connection with the history of the steam-engine. In that year Thomas Savery obtained a patent for raising water by steam. His was a modification of the idea described above. The boilers used would be of no value now, nevertheless the machine came into considerable use, and the world that learned so gradually became possessed with the idea that there was a utility in the pressure of steam. Savery's engine is said to have grown out of the accident of his throwing a flask containing a little wine on the fire at a tavern. Concluding immediately afterwards that he wanted it, he snatched it off of the fender and plunged it into a basin of water to cool it. The steam inside instantly condensing, the water rushed in and filled it as it cooled.

We now come to the beginning of the steam engine as we understand the term; the machine that involves the use of the cylinder and piston. These two features had been used in pumps long before, the atmospheric pump being one of the oldest of modern machines. The vacuum was known and utilized long before the cause of it was known.

But in the beginning it was not proposed to use steam in connection with the cylinder and piston which now really constitutes the steam-engine. Reverting again to the example of the gun, it was suggested to push a piston forward in a tube by the explosion of gunpowder behind it, or to repeat the Savery experiment with powder instead of steam. These ideas were those of about 1678-1685. The very earliest cylinder and piston engine was suggested by Denis Papin in 1690. These early inventors only went a portion of the way, and almost the entire idea of the steam-engine is of much later date. Mankind had then a singular gift of beginning at the wrong end. Every inventor now uses facts that seem to him to have been always known, and that are his by a kind of intuition. But they were all acquired by the tedious experience of a past that is distinguished by a few great names whose owners knew in their time perhaps one-tenth part as much as the modern inventor does, who is unconsciously using the facts learned by old experience. But the others began at the beginning.

In 1711, almost a hundred years after the arrival at Jamestown and Plymouth of the fathers of our present civilization, the steam-engine that is called Newcomen's began to be used for the pumping of water out of mines. This engine, slightly modified, and especially by the boy who invented the automatic cut-off for the steam valves, was a most rude and clumsy machine measured by our ideas. There appears to have been scarcely a single feature of it that is now visible in a modern engine. The cylinder was always vertical. It had the upper end open, and was a round iron vessel in which a plunger moved up and down. Steam was let in below this plunger, and the walking-beam with which it was connected by a rod had that end of it raised. When raised the steam was cut off, and all that was then under the piston was condensed by a jet of cold water. The outside air-pressure then acted upon it and pushed it down again. In this down-stroke by air-pressure the work was done. The far end of the walking-beam was even counter-weighted to help the steam-pressure. The elastic force of compressed steam was not depended upon, was hardly even known, in this first working and practical engine of the world. Every engine of that time was an experimental structure by itself. The boiler, as we use it, was unknown. Often it was square, stayed and braced against pressure in a most complicated way. Yet the Newcomen engine held its place for about seventy-five years; a very long time in our conception, and in view of the vast possibilities that we now know were before the science.

In the year 1760, James Watt, who was by occupation what is now known as a model-maker, and who lived in Glasgow, was called upon to repair a model of a Newcomen engine belonging to the university. While thus engaged he was impressed with the great waste of steam, or of time and fuel, which is the same thing, involved in the alternate heating and cooling of Newcomen's cylinder. To him occurred the idea of keeping the cylinder as hot as the steam used in it. Watt was therefore the inventor of the first of those economies now regarded as absolute requirements in construction. He made the first "steam-jacket," and was, as well, the author of the idea of covering the cylinder with a coat of wood, or other non-conductor. He contrived a second chamber, outside of the cylinder, where the then indispensable condensation should take place. Then he gave this cylinder for the first time two heads, and let out the piston-rod through a hole in the upper head, with packing. He used steam on the upper side of the piston as well as the lower, and it will be seen that he came very near to making the modern engine.

Yet he did not make it. He was still unable to dispense with the condensing and vacuum and air-pressure ideas. Acting for the first time in the line of real efficiency, he failed to go far enough to attain it. He made a double-acting engine by the addition of many new parts; he even attained the point of applying his idea to the production of circular motion. But he merely doubled the Newcomen idea. His engine became the Newcomen-Watt. He had a condensing chamber at each end of the stroke and could therefore command a reciprocating movement. The walking-beam was retained, not for the purpose for which it is often used now, but because it was indispensable to his semi-atmospheric engine.

It may seem almost absurd that the universal crank-movement of an engine was ever the subject of a patent. Yet such was the case. A man named Pickard anticipated Watt, and the latter then applied to his engines the "sun-and-planet" movement, instead of the crank, until the patent on the latter expired. The steam-engine marks the beginning of a long series of troubles in the claims of patentees.

Then he invented the "governor," a contrivance that has scarcely changed in form, and not at all in action, since it was first used, and is one of the few instances of a machine perfect in the beginning. Two balls hang on two rods on each side of an upright shaft, to which the rods are hinged. The shaft is rotated by the engine, and the faster it turns the more the two balls stand out from it. The slower it turns the more they hang down toward it. Any one can illustrate this by whirling in his hands a half-open umbrella. There is a connection between the movement of these balls and the throttle; as they swing out more they close it, as they fall closer to the shaft they open it. The engine will therefore regulate its own speed with reference to the work it has to do from moment to moment.

Through all these changes the original idea remained of a vacuum at the end of every stroke, of indispensable assistance from atmospheric pressure, of a careful use of the direct expansive power of steam, and of the avoidance of the high pressures and the actual power of which steam is now known to be safely capable. Then an almost unknown American came upon the scene. In English hands the story at once passes from this point to the experiments of Trevethick and George Stevenson with steam as applied to railway locomotion. But as Watt left it and Trevethick found it, the steam engine could never have been applied to locomotion. It was slow, ponderous, complicated and scientific, worked at low pressures, and Watt and his contemporaries would have run away in affright from the innovation that came in between them and the first attempts of the pioneers of the locomotive. This innovation was that of Evans, the American, of whom further presently.

The first steam-engine ever built in the United States was probably of the Watt pattern, in 1773. In 1776, the year of beginning for ourselves, there were only two engines of any kind in the colonies; one at Passaic, N. J., the other at Philadelphia. We were full of the idea of the independence we had won soon afterwards, but in material respects we had all before us.

In 1787, Oliver Evans introduced improvements in grain mills, and was generally efficient as one of the beginners in the field of American invention. Soon afterwards he is known to have made a steam-engine which was the first high-pressure double-acting engine ever made. The engine that used steam at each end of the cylinder with a vacuum and a condenser, was in this first instance, so far as any record can be found, supplanted by the engine of to-day. The reason of the delay it is difficult to account for on any other grounds than lack of boldness, for unquestionably the early experimenters knew that such an engine could be made. They were afraid of the power they had evoked. Such a machine may have seemed to them a willful toying with disaster. Their efforts were bent during many years toward rendering a treacherous giant useful, yet entirely harmless. Their boilers, greatly improved over those I have mentioned, never were such as were afterwards made to suit the high pressures required by the audacity of Hopkins. This audacity was the mother of the locomotive, and of that engine which almost from that date has been used for nearly every purpose of our modern life that requires power. The American innovation may have passed unnoticed at the time, but intentionally or otherwise it was imitated as a preliminary to all modern engines. Nearly a century passed between the making of the first practical engine and that one which now stands as the type of many thousands. But now every little saw-mill in the American woods could have, and finally did have, its little cheap, unscientific, powerful and non-vacuum engine, set up and worked without experience, and maintained in working order by an unskilled laborer. A thousand uses for steam grew out of this experiment of a Yankee who knew no better than to tempt fate with a high-pressure and speed and recklessness that has now become almost universal.

There was with Watt and his contemporaries apparently a fondness for cost and complications. Most likely the finished Watt engine was a handsome and stately machine, imposing in its deliberate movements. There is apparently nothing simpler than the placing of the head of the piston-rod between two guide-pieces to keep it in line and give it bearing. Yet we have only to turn back a few years and see the elaborate and beautiful geometrical diagram contrived by Watt to produce the same simple effect, and known as a "parallel motion." It kept its place until the walking-beam was cast away, and the American horizontal engine came into almost universal use.

The object of this chapter so far has been to present an idea of beginnings; of the evolution of the universal and indispensable machine of civilization. The steam-engine has given a new impetus to industry, and in a sense an added meaning to life. It has made possible most that was ever dreamed of material greatness. It has altered the destiny of this nation, and other nations, made greatness out of crude beginnings, wealth out of poverty, prosperity upon thousands of square miles of uninhabitable wilderness. It was the chiefest instrumentality in the widening of civilization, the bringing together of alien peoples, the dissemination of ideas. Electricity may carry the idea; steam carries the man with the idea. The crude misconceptions of old times existed naturally before its time, and have largely vanished since it came. Marco Polo and Mandeville and their kind are no longer possibilities. Applied to transportation, locomotion alone, its effects have been revolutionary. Applied to common life in its minute ramifications these effects could not have been believed or foretold, and are incredible. The thought might be followed indefinitely, and it is almost impossible to compare the world as we know it with the world of our immediate ancestors. Only by means of contrasts, startling in their details, can we arrive at an adequate estimate, even as a moral farce, of the power of steam as embodied in the modern engine in a thousand forms.

Perhaps it might be well to attempt to convey, for the benefit of the youngest reader, an idea of the actual working of the machine we call a steam-engine. There are hundreds of forms, and yet they are all alike in essentials. To know the principle of one is to know that of all. There is probably not an engine in the world in effective common use--the odd and unusual rotary and other forms never having been practical engines--that is not constructed upon the plan of the cylinder and piston. These two parts make the engine. If they are understood only differences in construction and detail remain.

Imagine a short tube into which you have inserted a pellet, or wad of any kind, so that it fits tolerably, yet moves easily back and forth in the bore of the tube. If this pellet or wad is at one end of the tube you may, by inserting that end in your mouth and putting air-pressure upon it, make it slide to the other end. You do not touch it with anything; you may push it back and forth with your breath as many times as you wish, not by blowing against it, so to speak, but by producing an actual air-pressure upon it which is confined by the sides of the tube and cannot go elsewhere. The only pressure necessary is enough to move the pellet.

Now, if you push this little pellet one way by the air-pressure from your mouth, and then, instead of reversing the tube in the mouth and pushing it back again in the same way, reverse the process and suck the air out from behind it, it comes back by the pressure of the outside atmosphere. This was the way the first steam engines worked. Their only purpose was to get the piston lifted, and air-pressure did all the actual work.

If you turn the tube, and put an air-pressure first at one end and then at the other, and pay no attention to vacuum or atmospheric pressure, you will have the principle of the later modern, almost universal, high-pressure, double-acting steam-engine.

But now you must imagine that the tube is fixed immovably, and that the air-pressure is constant in a pipe leading to the tube, and yet must be admitted first to one end of the tube and then to the other alternately, in order to push the pellet back and forth in it. It seems simple. Perhaps the young reader can find a way to do it, but it required about a hundred years for ingenious men to find out how to do precisely the same thing automatically. It involves the steam-chest and the slide-valve, and all other kinds of steam valves that have been invented, including the Corliss cut-off, and all others that are akin to it in object and action.

But now imagine the tube closed at each end to begin with, and the little moving pellet, or plunger, on the inside. To get the air into both ends of the tube alternately, and to use its pressure on each side of the pellet, we will suppose that the air-pipe is forked, and that one end of each fork is inserted into the side of the tube near the end, like the figure below, and imagine also that you have put a finger over each end of the tube.

We are now getting the air-pressure through the pipe in both ends of the tube alike, and do not move the pellet either way. To make it move we must do something more, and open one end of the tube, and close that fork of the air-pipe, and thus get all the pressure on one side of the pellet. Remove one finger from the end of the tube, and pinch the fork of the air-tube that is on that side. The pellet will now move toward that end of the tube which is open. Reverse the process, and it can be pushed back again with air-pressure to the other end, and so on indefinitely.

Let us improve the process. We will close each end of the tube permanently, and insert four cocks in the tube and forked pipe.

We are using air instead of steam, and the movement of these four cocks all at the same time, and the result of moving them, is precisely that of the slide-valve of a steam-engine. The diagrams of this slide-valve would be difficult to understand. The action of the cocks can be more readily understood, and the result, and even much of the action, is precisely the same.

But to make the arrangement entirely efficient we must go a little further into the construction of a steam-engine. The pellet in the tube has no connection with the outside, and we can get nothing from it. So we give it a stem, thus: and when we do so we change it into a piston and its rod. Where it passes through the stopper at the end of the tube it must pass air- tight. Then as we push the piston back and forth we have a movement that we can attach to machinery at the end of the rod, and get a result from. We also move the cocks, or valves, automatically by the movement of the rod.

Turning now to Fig. 3 again let us imagine a connection made between the rod and the end of the lever in Fig. 2. Now put on the air pressure, and when the piston has reached the right-hand end of the tube it automatically, by its connections, closes B. and opens A., and opens D. and closes C. The pellet will be pushed back in the tube and go to the other end of it, through the pressure coming against the piston through the part of the air tube where the cock D. is open. It reaches the left-hand end of the tube, and we must imagine that when it gets there it, in the same manner and by the proper connections, closes D., opens C., closes A. and opens B. If these mechanical movements are completed it must be plain that so long as the air pressure is continued in the forked pipe the piston will automatically cut off its supply and open its escape at each alternate end, and move back and forth. Any boy can see how a backward and forward movement may be made to give motion to a crank. All other details in an engine are questions of convenience in construction, and not questions of principle or manner of action.

THE AGE OF STEEL

The greatest progresses of the race are almost always unappreciated at the time, and are certainly undervalued, except by contrast and comparison. We must continually turn backward to see how far we have gone. An individual who is born into a certain condition thinks it as hard as any other until by experience and comparison he discovers what his times might have been. As for us, in the year 1894, we are not compelled to look backward very far to observe a striking contrast.

All the wealth of today is built upon the forests and prairies and swamps of yesterday, and we must take a wider and more comprehensive glance backward if we should wish to institute those comparisons which make contrasts startling.

We are accustomed to read and to hear of the "Age" of this or that. There was a "Stone" Age, beginning with the tribes to whom it came before the beginnings of their history, or even of tradition, and if we look far backward we may contrast our own time with the times of men who knew no metals. They were men. They lived and hoped and died as we do, even in what is now our own country. Often they were not even barbarians. They builded houses and forts, and dug drains and built aqueducts, and tilled the soil. They knew the value of those things we most value now, home and country; and they organized armies, and fought battles, and died for an idea, as we do. Yet all the time, a time ages long, the utmost help they had found for the bare and unaided hand was the serrated edge of a splintered flint, or the chance-found fragment beside a stream that nature, in a thousand or a million years of polishing, had shaped into the rude semblance of a hammer or a pestle. All men have in their time burned and scraped and fashioned all they needed with an astonishing faculty of making it answer their needs. They once almost occupied the world. Such were those who, so far as we know, were once the exclusive owners of this continent. They were an agricultural, industrious and home-loving people.

Then came, with a strange leaving out of the plentiful and easily worked metals which are the subject of this chapter, the great Age of Bronze. This next stage of progress after stone was marked by a skillful alloy, requiring even now some scientific knowledge in its compounding of copper and tin. A thousand theories have been brought forward to account for this hiatus in the natural stages of human progress, the truth probably being that both tin and copper are more fusible than iron-ores, and that both are found as natural metals. Some accident such as accounts for the first glass, some camp-fire unintended fusion, produced the alloy that became the metal of all the arms and arts, and so remained for uncounted centuries. In this connection it is declared that the Age of Bronze knew something that we cannot discover; the art of tempering the alloy so that it would bear an edge like fine steel. If this be true and we could do it, we should by choice supplant the subject of this chapter for a thousand uses. As the matter stands, and in our ignorance of a supposed ancient secret, the tempering of bronze has an effect precisely opposite to that which the process has upon steel.

Nevertheless, the old Age of Bronze had its vicissitudes. Those men knew nothing that we consider knowledge now. It was a time when some of the most splendid temples, palaces and pyramids were constructed, and these now lie ruined yet indestructible in the nooks and corners of a desert world. Perhaps the hard rock was chiselled with tools of tempered copper. The fact is of little importance now since the object of the art is almost unknown, and the scattered capitals and columns of Baalbeck are like monuments without inscriptions; the commemorating memorials of a memory unknown. The Age of Bronze and all other ages that have preceded ours lacked the great essentials that insure perpetuity. The Age of Steel, that came last, that is ours now; a degenerate time by all ancient standards; has for its crowning triumph a single machine which is alone enough to satisfy the union of two names that are to us what Caster and Pollux were to the bronze-armed Roman legions of the heroic time--the modern power printing-press.

It may be well to ask and answer the question that at the first view may seem to the reader almost absurd. What is steel? The answer must, in the majority of instances, be given in accordance with the common conception; which is that it is not iron, yet very like it. The old classification of the metal, even familiarly known, needs now to be supplemented, since it does not describe the modern cast and malleable compounds of iron, carbon and metalloids used for structural purposes, and constituting at least three-fourths of the metal now made under the name of steel. The old term, steel, meant the cast, but malleable, product of iron, containing as much carbon as would cause the metal to harden when heated to redness and quenched in water. It must also be included in the definition that the product must be as free as possible from all admixtures except the requisite amount of carbon. This is "tool" steel.

And here occurs a strange thing. A skill in chemistry, the successor of alchemy, is the educational product of the highest form of civilization.

The ordinary test applied to distinguish wrought iron from steel is to ascertain whether the metal hardens with heating and suddenly cooling in cold water, becoming again softened on reheating and cooling slowly. If it does this it is steel of some quality, good or bad; if not, it is iron.

The first mention of iron-ore in America is by Thomas Harriot, an English writer of the time of Raleigh's first colonies. He wrote a history of the settlement on Roanoke Island, in which he says: "In two places in the countrey specially, one about foure score and the other six score miles from the port or place where wee dwelt, wee founde neere the water side the ground to be rockie, which by the triall of a minerall man, was found to hold iron richly. It is founde in manie places in the countrey else." Harriot speaks further of "the small charge for the labour and feeding of men; the infinite store of wood; the want of wood and the deerness thereof in England." It was before the day of coal and coke, or of any of the processes known now. The iron mines of Roanoke Island were never heard of again.

Iron-ore in the colonies is again heard of in the history of Jamestown, in 1607. A ship sailed from there in 1608 freighted with "iron-ore, sassafras, cedar posts and walnut boards." Seventeen tons of iron were made from this ore, and sold for four pounds per ton. This was the first iron ever made from American ores. The first iron-works ever erected in this country were, of course almost, burned by the Indians, in 1622, and in connection three hundred persons were killed.

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