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CHAPTER VII.
STEAM AND STEAM ENGINES

 
"Soon shall thy arm, unconquered steam! afar
Drag the slow barge, or drive the rapid car;
Or in wide waving wings expanded bear
The flying chariot through the field of air."
 

Thus sang the poet prophet, the good Dr. Darwin of Lichfield, in the eighteenth century. Newcomen and Watt had not then demonstrated that steam was not unconquerable, but the hitching it to the slow barge and the rapid car was yet to come. It has come, and although the prophecy is yet to be rounded into fulfilment by the driving of the "flying chariot through the field of air," that too is to come.

The prophecy of the doctor poet was as suggestive of the practical means of carrying it into effect as were all the means proposed during the first seventeen centuries of the Christian Era for conquering steam and harnessing it as a useful servant to man.

Toys, speculations, dreams, observations, startling experiments, these often constitute the framework on which is hung the title of Inventor; but the nineteenth century has demanded a better support for that proud title. He alone who first transforms his ideas into actual work and useful service in some field of man's labor, or clearly teaches others to do so, is now recognised as the true inventor. Tested by this rule there was scarcely an inventor in the field of steam in all the long stretches of time preceding the seventeenth century. And if there were, they had no recording scribes to embalm their efforts in history.

We shall never know how early man learned the wonderful power of the spirit that springs from heated water. It was doubtless from some sad experience in ignorantly attempting to put fetters on it.

The history of steam as a motor generally commences with reference to that toy called the aeolipile, described by Hero of Alexandria in a treatise on pneumatics about two centuries before Christ, and which was the invention of either himself or Ctesibius, his teacher.

This toy consisted of a globe pivoted on two supports, one of which was a communicating pipe leading into a heated cauldron of water beneath. The globe was provided with two escape pipes on diametrically opposite sides and bent so as to discharge in opposite directions. Steam admitted into the globe from the cauldron escaped through the side pipes, and its pressure on these pipes caused the globe to rotate.

Hero thus demonstrated that water can be converted into steam and steam into work.

Since that ancient day Hero's apparatus has been frequently reinvented by men ignorant of the early effort, and the principle of the invention as well as substantially the same form have been put into many practical uses. Hero in his celebrated treatise described other devices, curious siphons and pumps. Many of them are supposed to have been used in the performance of some of the startling religious rites at the altars of the Greek priests.

From Hero's day the record drops down to the middle ages, and still it finds progress in this art confined to a few observations and speculations. William of Malmesbury in 1150 wrote something on the subject and called attention to some crude experiments he had heard of in Germany. Passing from the slumber of the middle ages, we are assured by some Spanish historians that one Blasco de Garay, in 1543, propelled a ship having paddle wheels by steam at Barcelona. But the publication was long after the alleged event, and is regarded as apocryphal.

Observations became more acute in the sixteenth and seventeenth centuries, experiments more frequent, and publications more full and numerous.

Cardan Ramelli and Leonardo da Vinci, learned Italians, and the accomplished Prof. Jacob Besson of Orleans, France, all did much by their writings to make known theoretically the wonderful powers of steam, and to suggest modes of its practical operation, in the latter part of the sixteenth century.

Giambattista della Porta, a gentleman of Naples, possessing high and varied accomplishments in all the sciences as they were known at that day, 1601, and who invented the magic-lantern and camera obscura, in a work called Spiritalia, described how steam pressure could be employed to raise a column of water, how a vacuum was produced by the condensation of steam in a closed vessel, and how the condensing vessel should be separated from the boiler. Revault in France showed in 1605 how a bombshell might be exploded by steam.

Salomon de Caus, engineer and architect to Louis XIII, in 1615 described how water might be raised by the expansion of steam.

In 1629 the Italian, Branco, published at Rome an account of the application of a steam jet upon the vanes of a small wheel to run it, and told how in other ways Hero's engine might be employed for useful purposes.

The first English publication describing a way of applying steam appeared in 1630 in a patent granted to David Ramseye, for a mode of raising water thereby. This was followed by patents to Grant in 1632 and to one Ford in 1640. During that century these crude machines were called "fire engines." It seems to have been common in some parts of Europe during the seventeenth century to use a blast of steam to improve the draft of chimneys and of blast furnaces. This application of steam to smoke and smelting has been frequently revived by modern inventors with much flourish of originality.

It is with a certain feeling of delight and relief, after a prolonged search through the centuries for some evidence of harnessing this mighty agent to man's use, that we come to the efforts of the good Marquis of Worcester – Edward Somerset. He it was who in 1655 wrote of the Inventions of the Sixteenth Century. He afterwards amplified this title by calling his book A Century of Names and Scantlings of such Inventions as at present I call to mind to have tried and perfected, etc.

There are about one hundred of these "Scantlings," and his descriptions of them are very brief but interesting. Some, if revived now and put to use, would throw proposed flying machines into the background, as they involved perpetual motion.

But to his honor be it said that he was the first steam-engine builder. A patent was issued to him in 1663. It was about 1668 that he built and put in successful operation at Raglan Castle at Vauxhall, near London, a steam engine to force water upward. He made separate boilers, which he worked alternately, and conveyed the steam from them to a vessel in which its pressure operated to force the water up. Unfortunately he did not leave a description of his inventions sufficiently full to enable later mechanics to make and use them. He strove in vain to get capital interested and a company formed to manufacture his engines. The age of fear and speculation as to steam ceased when the Marquis set his engine to pumping water, and from that time inventors went on to put the arm of steam to work.

In 1683 Sir Samuel Morland commenced the construction of the Worcester engines for use and sale; Hautefeuille of France taught the use of gas, described how gas as well as steam engines might be constructed, and was the first to propose the use of the piston. The learned writings of the great Dutch scientist and inventor, Huygens, on heat and light steam and gas, also then came forth, and his assistant, the French physicist and doctor, Denis Papin, in 1690, proposed steam as a universal motive power, invented a steam engine having a piston and a safety valve, and even a crude paddle steamer, which it is said was tried in 1707 on the river Fulda. Then in 1698 came Thomas Savery, who patented a steam engine that was used in draining mines.

The eighteenth century thus commenced with a practical knowledge of the power of steam and of means for controlling and working it.

Then followed the combined invention of Newcomen, Cawley and Savery, in 1705, of the most successful pumping engine up to that time. In this engine a cylinder was employed for receiving the steam from a separate boiler. There was a piston in the cylinder driven up by the steam admitted below it, aided by a counterpoise at one end of an engine beam. The steam was then cut off from the boiler and condensed by the introduction beneath the piston of a jet of water, and the condensed steam and water drawn off by a pipe. Atmospheric pressure forced the piston down. The piston and pump rods were connected to the opposite ends of a working beam of a pumping engine, as in some modern engines. Gauge cocks to indicate the height of water, and a safety valve to regulate the pressure of steam, were employed. Then came the ingenious improvement of the boy Humphrey Potter, connecting the valve gear with the engine beam by cords, so as to do automatically what he was set to do by hand, and the improvement on that of the Beighton plug rod. Still further improved by others, the Newcomen engine came into use through out Europe.

Jonathan Hulls patented in England in 1736 a marine steam engine, and in 1737 published a description of a Newcomen engine applied to his system for towing ships. William Henry, of Pennsylvania, tried a model steamboat on the Conestoga river in 1763.

This was practically the state of the art, in 1763, when James Watt entered the field. His brilliant inventions harnessed steam to more than pumping engines, made it a universal servant in manifold industries, and started it on a career which has revolutionized the trade and manufactures of the world.

To understand what the nineteenth century has done in steam motive power we must first know what Watt did in the eighteenth century, as he then laid the foundation on which the later inventions have all been built.

Taking up the crude but successful working engine of Newcomen, a model of which had been sent to him for repairs, he began an exhaustive study of the properties of steam and of the means for producing and controlling it. He found it necessary to devise a new system.

Watt saw that the alternate heating and cooling of the cylinder made the engine work slowly and caused an excessive consumption of steam. He concluded that "the cylinder should always be as hot as the steam that entered it." He therefore closed the cylinder and provided a separate condensing vessel into which the steam was led after it raised the piston. He provided an air-tight jacket for the cylinder, to maintain its heat. He added a tight packing in the cylinder-head for the piston-rod to move through, and a steam-tight stuffing-box on the top of the cylinder. He caused the steam to alternately enter below and above the piston and be alternately condensed to drive the piston down as well as up, and this made the engine double-acting, increasing its power and speed. He converted the reciprocating motion of the piston into a rotary motion by the adoption of the crank, and introduced the well-known parallel motion, and many other improvements. In short, he demonstrated for the first time by a practical and efficient engine that the expansive force of steam could be used to drive all ordinary machinery. He then secured his inventions by patents against piracy, and sustained them successfully in many a hard-fought battle. It had taken him the last quarter of the 18th century to do all these things.

Watt was the proper precursor of the nineteenth century inventions, as in him were combined the power and attainments of a great scientist and the genius of a great mechanic. The last eighteen years of his life were passed in the 19th century, and he was thus enabled to see his inventions brought within its threshold and applied to those arts which have made this age so glorious in mechanical achievements.

Watt so fitly represents the class of modern great inventors in his character and attainments that the description of him by Sir Walter Scott is here pertinent as a tribute to that class, and as a delineation of the general character of those benefactors of his race of which he was so conspicuous an example: —

Says Sir Walter: —

"Amidst this company stood Mr. Watt, the man whose genius discovered the means of multiplying our national resources to a degree, perhaps, even beyond his own stupendous powers of calculation and combination; bringing the treasures of the abyss to the summit of the earth – giving to the feeble arm of man the momentum of an Afrite – commanding manufactures to rise – affording means of dispensing with that time and tide which wait for no man – and of sailing without that wind which defied the commands and threats of Xerxes himself. This potent commander of the elements – this abridger of time and space – this magician, whose cloudy machinery has produced a change in the world, the effects of which, extraordinary as they are, are perhaps only beginning to be felt – was not only the most profound man of science, the most successful combiner of powers and calculator of numbers, as adapted to practical purposes, was not only one of the most generally well-informed, but one of the best and kindest of human beings."

The first practical application of steam as a working force was to pumping, as has been stated. After Watt's system was devised, suggestions and experiments as to road locomotives and carriages were made, and other applications came thick and fast. A French officer, Cugnot, in 1769 and 1770, was the first to try the road carriage engine. Other prominent Frenchmen made encouraging experiments on small steamboats – followed in 1784-86 by James Rumsey and John Fitch in America in the same line. Watt patented a road engine in 1784. About the same time his assistant, Murdock, completed and tried a model locomotive driven by a "grasshopper" engine. Oliver Evans, the great American contemporary of Watt, had in 1779 devised a high-pressure non-condensing steam engine in a form still used. In 1786-7 he obtained in Pennsylvania and Maryland patents for applying steam to driving flour mills and propelling waggons. Also about this time, Symington, the Scotchman, constructed a working model of a steam carriage, which is still preserved in the museum at South Kensington, London. Symington and his fellow Scotchmen, Miller and Taylor, in 1788-89 also constructed working steamboats. In 1796 Richard Trevithick, a Cornish marine captain, was producing a road locomotive. The century thus opened with activity in steam motive power. The "scantlings" of the Marquis of Worcester were now being converted into complete structures. And so great was the activity and the number of inventors that he is a daring man who would now decide priority between them. The earliest applications in this century of steam power were in the line of road engines.

On Christmas eve of 1801, Trevithick made the initial trip with the first successful steam road locomotive through the streets of Camborne in Cornwall, carrying passengers. In one of his trips he passed into the country roads and came to a tollgate through which a frightened keeper hastily passed him without toll, hailing him as the devil.

Persistent efforts continued to be made to introduce a practical steam road carriage in England until 1827. After Trevithick followed Blenkinsop, who made a locomotive which ran ten miles an hour. Then came Julius Griffith, in 1821, of Brompton, who patented a steam carriage which was built by Joseph Bramah, one of the ablest mechanics of his time. Gordon, Brunton and Gurney attempted a curious and amusing steam carriage, resembling a horse in action – having jointed legs and feet, but this animal was not successful. Walter Hancock, in 1827, was one of the most persistent and successful inventors in this line; but bad roads and an unsympathetic public discouraged inventors in their efforts to introduce steam road carriages, and their attention was turned to the locomotive to run on rails or tracks especially prepared for them. Wooden and iron rails had been introduced a century before for heavy cars and wagons in pulling loads from mines and elsewhere, but when at the beginning of the century it had been found that the engines of Watt could be used to drag such loads, it was deemed necessary to make a rail having its top surface roughened with ridges and the wheels of the engine and cars provided with teeth or cogs to prevent anticipated slipping.

In England, Blackett and George Stephenson discovered that the adhesion of smooth wheels to smooth rails was sufficient. Without overlooking the fact that William Hendley built and operated a locomotive called the Puffing Billy in 1803, and Hackworth one a little later, yet to the genius of Stephenson is due chiefly the successful introduction of the modern locomotive. His labours and inventions continued from 1812 for twenty years, and culminated at two great trials: the first one on the Liverpool and Manchester Railway in 1829, when he competed with Hackworth and Braithwaite and Ericsson, and with the Rocket won the race; and the second at the opening of the same road in 1830, when with the Northumbrian, at the head of seven other locomotives and a long train of twenty-eight carriages, in which were seated six hundred passengers, he ran the train successfully between the two towns.

On this occasion Mr. Huskisson, Home Secretary in the British Cabinet, while the cars were stopping to water the engines, and he was out on the track talking with the Duke of Wellington, was knocked down by one of the engines and had one of his legs crushed. Placed on board of the Northumbrian, it was driven at the rate of thirty-six miles an hour by Stephenson to Eccles. Mr. Huskisson died there that night. This was its first victim, and the greatest speed yet attained by a locomotive.

The year 1829 therefore can be regarded as the commencement of the life of the locomotive for transportation of passengers. The steam blast thrown into the smokestack by Hackworth, the tubular boiler of Seguin and the link motion of Stephenson were then, as they now are, the essential features of locomotives.

In the meantime America had not been idle. The James Watt of America, Oliver Evans, in 1804 completed a flat-bottomed boat to be used in dredging at the Philadelphia docks, and mounting it on wheels drove it by its own steam engine through the streets to the river bank. Launching the craft, he propelled it down the river by using the same engine to drive the paddle wheels. He gave to this engine the strange name of Oruktor Amphibolos.

John C. Stevens of New Jersey was, in 1812, urging the legislature of the State of New York to build railways, and asserting that he could see nothing to hinder a steam carriage from moving with a velocity of one hundred miles an hour. In 1829 George Stephenson in England had made for American parties a locomotive called The Stourbridge Lion, which in that year was brought to America and used on the Delaware and Hudson R. R. by Horatio Allen. Peter Cooper in the same year constructed a locomotive for short curves, for the Baltimore and Ohio Railroad.

Returning now to steam navigation: – Symington again entered the field in 1801-2 and constructed for Lord Dundas a steamboat, named after his wife, the Charlotte Dundas, for towing on a canal, which was successfully operated.

Robert Fulton, an American artist, and subsequently a civil engineer, built a steamboat on the Seine in 1803, assisted by R. Livingston, then American Minister to France. Then in 1806 Fulton, having returned to the United States, commenced to build another steamboat, in which he was again assisted by Livingston, and in which he placed machinery made by Boulton and Watt in England. This steamboat, named the Clermont, was 130 ft. long, 18 ft. beam, 7 ft. depth and 160 tons burden. It made its first trip on the Hudson, from New York to Albany and return, in August, 1807, and subsequently made regular trips. It was the first commercially successful steamboat ever made, as George Stephenson's was the first commercially successful locomotive. In the meantime Col. John Stevens of New Jersey was also at work on a steamboat, and had in 1804 built such a boat at his shops, having a screw propeller and a flue boiler. Almost simultaneously with Fulton he brought out the Phœnix, a side-wheel steamer having hollow water lines and provided with feathering paddle wheels, and as Fulton and Livingston had a monopoly of the Hudson, Stevens took his boat by sea from New York around to Delaware bay and up the Delaware river. This was in 1808, and was the first sea voyage ever made by a steam vessel.

Transatlantic steamship navigation was started in 1819. A Mr. Scarborough of Savannah, Ga., in 1818 purchased a ship of about three hundred and fifty tons burden, which was named the Savannah. Equipped with engine and machinery it steamed out of New York Harbour on the 27th day of March, 1819, and successfully reached Savannah, Georgia. On the 20th of May in the same year she left Savannah for Liverpool, making the trip in 22 days. From Liverpool she went to Copenhagen, Stockholm, St. Petersburg, Cronstadt and Arundel, and from the latter port returned to Savannah, making the passage in twenty-five days.

But Scottish waters, and the waters around other coasts of the British Islands, had been traversed by steamboats before this celebrated trip of the Savannah. Bell's steamboat between Glasgow and Greenock in 1812 was followed by five others in 1814; and seven steamboats plied on the Thames in 1817.

So the locomotives and the steamboats and steamships continued to multiply, and when the first forty years of the century had been reached the Iron Horse was fairly installed on the fields of Europe and America, and the rivers and the oceans were ploughed by its sisters, the steam vessels.

It was in 1840 that the famous Cunard line of transatlantic steamers was established, soon followed by the Collins line and others.

A few years before, John C. Stevens in America and John Ericsson in England had brought forward the screw propeller; and Ericsson was the first to couple the engine to the propeller shaft. It succeeded the successful paddle wheels of Fulton in America and Bell in England.

The nineteenth century is the age of kinetic energy: the energy of either solid, liquid, gaseous or electrical matter transformed into useful work.

It has been stated by that eminent specialist in steam engineering, Prof. R. H. Thurston, that "the steam engine is a machine which is especially designed to transform energy originally dormant or potential into active and useful available kinetic energy;" and that the great problem in this branch of science is "to construct a machine which shall in the most perfect manner possible convert the kinetic energy of heat into mechanical power, the heat being derived from the combustion of fuel, and steam being the receiver and conveyor of that heat."

Watt and his contemporaries regarded heat as a material substance called "Phlogiston." The modern kinetic theory of heat was a subsequent discovery, as elsewhere explained.

The inventors of the last part of the eighteenth century and of the nineteenth century have directed their best labours to construct an engine as above defined by Thurston.

First as to the boiler: Efforts were made first to get away from the little old spherical boiler of Hero. In the 18th century Smeaton devised the horizontal lengthened cylindrical boiler traversed by a flue. Oliver Evans followed with two longitudinal flues. Nathan Read of Salem, Massachusetts, in 1791, invented a tubular boiler in which the flues and gases are conducted through tubes passing through the boiler into the smokestack. Such boilers are adapted for portable stationary engines, locomotives, fire and marine engines, and the fire is built within the boiler frame. Then in the 19th century came the use of sectional boilers – a combination of small vessels instead of a large common one, increasing the strength while diminishing capacity – to obtain high pressure of steam. Then came improved weighted and other safety valves to regulate and control this pressure. The compound or double cylinder high-pressure engine of Hornblower of England, in 1781, and the high-pressure non-condensing steam engine devised by Evans in 1779, were reconstructed and improved in the early part of the century.

To give perfect motion and the slightest friction to the piston; to regulate the supply of steam to the engine by proper valves; to determine such supply by many varieties of governors and thus control the speed; to devise valve gear which distributes the steam through its cycles of motion by which to admit the steam alternately to each end of the steam cylinder as the piston moves backward and forward, and exhaust valves to open and close the parts through which the steam escapes; to automatically operate such valves; to condense the escaping steam and to remove the water of condensation; to devise powerful steam brakes – these are some of the important details on which inventors have exercised their keenest wits. Then again the extensive inventions of the century have given rise to a great classification to designate their forms or their uses: condensing and non-condensing, high-pressure or low-pressure – the former term being applied to engines supplied with steam of 50 lbs. pressure to the square inch and upward, and the latter to engines working under 40 lbs. pressure – and the low pressure are nearly always the condensing and the high pressure the non-condensing; reciprocating and rotary – the latter having a piston attached to a shaft and revolving within a cylinder of which the axis is parallel with the axis of rotation of the piston.

Direct acting, where the piston rod acts directly upon the connecting rod and through it upon the crank, without the intervention of a beam or lever; oscillating, in which the piston rods are attached directly to the crank pin and as the crank revolves the cylinder oscillates upon trunnions, one on each side of it, through which the steam enters and leaves the steam chest.

Then as to their use, engines are known as stationary, pumping, portable, locomotive or marine.

The best-known engine of the stationary kind is the Corliss, which is very extensively used in the United States and Europe.

Among other later improvements is the duplex pumping engine, in which one engine controls the valve of the other; compensating devices for steam pumping, by which power is accumulated by making the first half of the stroke of the steam piston assist in moving the piston the other half of the stroke during the expansion of steam; steam or air hand hammers on which the piston is the hammer and strikes a tool projecting through the head into the cylinder; rock drilling, in which the movement of the valves is operated by the piston at any portion of its stroke; shaft governors, in which the eccentric for operating the engine valves is moved around or across the main or auxiliary shaft; multiple cylinders, in which several cylinders, either single or double, are arranged to co-operate with a common shaft; impact rotary, known as steam turbines, a revival in some respects of Hero's engine. And then, finally, the delicate and ingenious bicycle and automobile steam engines.

Then there are steam sanding devices for locomotives by which sand is automatically fed to the rails at the same time the air brake is applied.

Starting valves used for starting compound locomotives on ascending steep grades, in which both low and high pressure cylinders are supplied with live steam, and when the steam, exhausted from either high or low pressure cylinders into the receivers, has reached a predetermined pressure, the engine works on the compound principle. Single acting compound engines, in which two or more cylinders are arranged tandem, the steam acting only in one direction, and the exhaust steam of one acting upon the piston in the cylinder next of the series, are arranged in pairs, so that while one is acting downward the other is acting upward.

Throttle valves automatically closed upon the bursting of a pipe, or the breaking of machinery, are operated by electricity, automatically, or by hand at a distance.

Napoleon, upon his disastrous retreat from Moscow, anxious to reach Paris as soon as possible, left his army on the way, provided himself with a travelling and sleeping carriage, and with relays of fresh horses at different points managed, by extraordinary strenuous efforts day and night, to travel from Smorgoni to Paris, a distance of 1000 miles, between the 5th and 10th of December, 1812. This was at the average rate of about two hundred miles a day, or eight or nine miles an hour. It was a most remarkable ride for any age by horse conveyance.

Within the span of a man's life after that event any one could take a trip of that distance in twenty-four hours, with great ease and comfort, eating and sleeping on the car, and with convenient telegraph and telephone stations along the route by which to comunicate by pen, or word of mouth, with distant friends at either end of the journey.

If Napoleon had deemed it best to have continued his journey across the Atlantic to America he would have been compelled to pass several weeks on an uncomfortable sailing vessel. Now, a floating palace would await him which would carry him across in less than six days.

Should mankind be seized with a sudden desire to replace all the locomotives in the world by horse power it would be utterly impossible to do it. It was recently estimated that there were one hundred and fifty thousand locomotives in use on the railroads of the world; and as a fair average would give them five hundred horse power each, it will be seen that they are the equivalent of seventy-five million horses.

Space and time will not admit of minute descriptions, or hardly a mention, of the almost innumerable improvements of the century in steam. Having seen the principles on which these inventions have been constructed, enumerated the leading ones and glanced at the most prominent facts in their history, we must refer the seeker for more particulars to those publications of modern patent offices, in which each regiment and company of this vast army is embalmed in its own especial and ponderous volume.