Achievements Of The 19th Century:
A Century Of Achievement
Light And Heat Including Photography
Mining And Metallurgy
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( Originally Published Early 1900's )
"Give me a fulcrum on which to rest, and I will move the earth," said Archimedes when he discovered the lever. The modern engineer has found a standing point and he literally moves the earth not, it is true, in its place among the stars, but in that he brings every part of the universe nearer to the other and bends the forces of nature to his own purposes. The progress of the science of engineering is shown by its specialization during the Century. Mining and electrical engineering are treated elsewhere, Here it is the intention to tell of the progress in civil engineering during one hundred years and also to trace the development of steam, gas, and water power by the mechanical engineer.
All industries are indebted to the engineer. Civil engineering ranks among the learned professions, and mechanical engineering has ceased to be classed as a trade. It is the engineer, that magician of the Nineteenth Century, who binds the world together with the steel rails of the railway and the electric wire of the telegraph. He builds mammoth machines which will crush a ton of granite or crack an egg with equal ease; he has made use of the secrets of the elements, and realizes the imagery of Job in that he measures the mountains and rides upon the whirlwind. Gleaning the theories and facts from the scientists, who ferret out the secrets of nature, he makes use of them for the benefit of industry. No problem daunts the engineer of to-day; no feat is so impossible that he is not ready to essay it. He annihilates space and matter. The spirit of the mountain and the demon of the deep have not terrified him. The deepest valleys and the highest mountains are his playthings ; he bridges the one and tunnels through the bowels of, the other. He lifts great masses weighing thousands of tons with the ease with which a man will lift his finger. The feats fabled of the eastern genii are eclipsed by his everyday performances. "The high object of our profession is to consider and determine the most economic use of time, power, and matter," said a famous American engineer. That there will be further progress in this direction is certain, but it will be a marvelous Century that can show half so great a progress as has been made in that which is now closing.
To no industry has the engineer given a greater share of his art than to that of perfecting everything connected with railroading, and it is chiefly in the United States that this development has taken place. The steel rail as we know it today is in itself a wonderful piece of engineering. Thirty-five years ago the rail was of wrought-iron and shaped like a pear-head, but its evolution under the hands of the engineer has made it of steel and fitted it in every way for the work that it has to perform. Simple as it it, there is a reason for every curve, dimension and angle. It is made expressly for the purpose of sustaining its heavy loads and standing the impact of the count-less blows it receives.
So, too, the location of the railroad and the determination of exactly where every foot of the track shall be laid is an engineering feat. In the early days it was thought impossible for a locomotive to climb grades. The engineer has found just what grades the locomotive will climb and locates his track accordingly. Tunnels and great rivers were supposed to present practically unsurmountable obstacles, but the patient work of the engineer has shown that the greatest mountains might be pierced and the greatest chasms bridged. Railways can be built wherever it is profitable to build them.
Engineers of the olden time worked with stone, while those of to-day use steel. Fifty years ago bridges were built almost entirely of wood and stone. As long ago as 1779 the first iron bridge in England was built, and with 100-foot span and 370 tons of iron used in construction, it was the wonder of a generation, although it seems puny enough compared to the great Forth bridge of to-day, with 51,000 tons of steel. How conditions have changed since 1779 is shown by the fact that since 187o it has been a law in Russia that no bridges shall be made of wood. Yet the Howe wooden truss bridge of 184o was regarded as a wonder in its day, and some of them are still doing excellent service, the most famous being Wernberg's "Colossus," with 240 feet span over the Schuylkill.
Small streams were bridged at first and then the larger rivers were crossed, until now there is talk of bridging the English channel, making a railway journey possible from London to Paris, and the bridge would probably be built were it not that it would destroy the military advantages possessed by England through its insular position. In the United States alone there are now over 3,000 miles of bridgework, enough to form a highway across the Continent. This progress has been made possible by the use of iron and steel, the application of new theories of forces. The first attempt to use iron exclusively for long spans was the tubular bridge. Stephenson and Harrison had finished in 1849 the high-level bridge at Newcastle-on-Tyne. The first iron bridge in the United States was built at Frankfort, N. Y., in 1840.
By the introduction of the suspension bridge a great stride was made in bridge-building. Telford, a Scotch engineer, designed the first bridge across the Menai Straits in 1818, and it was opened in 1826, with a span of 579 feet and a roadway 100 feet above the water level. Other suspension bridges followed of increasing size. The general principle of the suspension bridge is exemplified in a chain hanging between two fixed points on the same level. If two chains were placed parallel to each other a roadway for a bridge might be formed by laying planks across it, but the ascent and descent would be necessarily steep. No amount of force could stretch the chains perfectly level, as even a small piece of straight cord cannot be stretched horizontally in a perfectly straight line. It was a happy idea to hang the roadway from the chains, for then the roadway would remain perfectly level if built so as to be level after the curve had been figured. The suspension bridge built by Roebling in 1852 had a span of 800 feet. It was followed by the Clifton bridge, opened in 1864. The Clifton bridge at Niagara Falls, and the bridges at Pittsburg and Cincinnati are of this type. The largest of all is the Brooklyn bridge, erected at a cost of $15,500,000, and having a clear water-way of 1,595 1-2 feet. It was begun in 1870 and opened May 24, 1883. Each cable contains 5,296 parallel (not twisted) galvanized steel oil coated wire, closely wrapped into a solid cylinder 15 3-4 inches in diameter, and the permanent weight suspended from these gigantic cables is 14,680 tons.
The favorite form of bridge-building at present is the cantilever system, the first metal bridge of that type being Shaler Smith's cantilever over the Kentucky River, erected in 1877. The principle of the cantilever is very simple. A powerful structure of steel, in shape not unlike the walking-beam of a paddle steamer, rests upon a pier. The weight on one side balances that on the other, but the arms of the two cantilevers do not meet. Imagine an engine's walking beam thirteen hundred feet long almost a quarter of a mile resting upon its center so that it projects in either direction 675 feet. Next fancy two such cantilevers so placed that their ends leave an abyss of 350 feet between them. This space is filled with an ordinary girder bridge, the ends of the two cantilevers serving as piers. The Forth bridge, built on this principle and opened in 189o, is the largest spanned bridge, having a length of 8,098 feet. It is composed of three double cantilevers; a central one of 1,62o feet resting on a pier built on the Island of Inchgarvie, two 1,514 feet in length joined to the central cantilever by girders of 350 feet span. The highest elevation of the bridge is 361 feet over the piers. Fifty-one thousand tons of steel were used in the construction of the bridge and fifty-six lives were lost during its erection, which occupied seven years and gave employment to as many as 5,000 men at one time. The total cost of this bridge, which is across the Firth of Forth at Queensbury, Scotland, was $16,000,000. The bridge at Memphis, Tenn., is the longest cantilever bridge in the United States, the greatest of its three spans being 720 feet.
Improvements in sinking the foundations have been nearly as great as those in raising the superstructure. The caisson is an application of the diving-bell that has simplified the work of sinking piers, and a German inventor has recently devised a process by which soft earth can be frozen and then dug out as if it were solid rock.
Modern engineering has made tunneling a comparatively simple operation. The tunnel is as old as the bridge, but its development has been no less remarkable. The early tunnels in the Century required the expenditure of an enormous amount of time, but new devices for rock-boring and the removal of soft earth have simplified matters. One of the earliest known tunnels, said to have been constructed to drain the plateau on which stands the City of Mexico, pierced the Nochistengo ridge for six miles. It was destroyed during a flood and was replaced by an open cut in 1608. But it required more than a century to build that tunnel with the devices then in the possession of engineers. The work was done almost entirely by hand and although the workmen were paid only 9 cents a day, the cost was $6,000,000. Aside from the free workmen all convicts sentenced to hard labor were put to work on the tunnel, which cost the lives of more than 100,000 workmen.
Nowadays machinery has replaced hand labor to a great extent, and there is no such great sacrifice of men required. This has made possible the building of tunnels of great length. The machine rock drill, invented by J. J. Couch, an American, in 1849, was first used in tunneling Mont Cenis, and made possible the Hoosac tunnel. Mont Cenis tunnel was long one of the wonders of the world. Nearly eight miles in length, it extends from Madane to Bardonneche under the Col de Frejus. The work was begun in 1857, with rock-boring machines, but these proving impractical, for four years the workmen drilled holes and blasted the rock by manual labor. Improvements in the machinery invented by Couch then made possible the use of machinery. Before the ma-chines were employed progress could be made at the rate of eighteen inches per day; towards the close, when the rock-boring machinery was in full working order, as much as 400 feet per month was excavated. From 1857 to 186o by hand labor alone 1,646 meters were excavated; from 1861 to 1870 the remaining 10,587 meters were completed by machine.
Most remarkable of completed tunnels is the St. Gothard, piercing the Alps. Work was begun in September, 1872, at each end, and it is a remarkable feat of civil engineering that the two openings met, in spite of the difficulty of the survey, with a variation of only 2 inches horizontally and 13 inches laterally. The tunnel is 9 I-2 miles long and cost about $700 per lineal yard. The first passenger train ran through the tunnel on November I, 1881, thus making possible the passing of the Alps at a point where before it had been possible only to mountaineers. Hannibal himself could not have led an army over the Alps at that point. The motive power of the rock-drilling machines was actuated, as was the case with the Mont Cenis tunnel, by compressed air, and the power used for compressing the air was a head of water.
The Simplon tunnel, though begun in this Century, will not be completed until the next. It will supersede the Simplon Pass road, begun in 1800 by Napoleon, who wished a military road to Italy and built it in six years, at an expenditure of $4,000,000 and the loss of innumerable lives. The Simplon tunnel will be 12 I-4 miles long, making it the longest in the world. Brandt rotary hydraulic drilling machines are to be used, and the pressure will be from 1,000 to 1,500 pounds to the square inch. Six or eight machines will be used at each heading. The Brandt machine has three cutting points like claws, with a lightly rotary movement, and works by hydraulic pressure.
The rock-boring machine known as the Burleigh, perfected in 1837, gave a great impetus to tunneling. It looks like a big syringe, supported upon a tripod, and is worked by compressed air. It eats holes two inches in diameter in solid granite, and makes honeycomb of it as easily as a schoolboy would demolish a small sponge cake. It pounds away at the rate of 200 strokes a minute, in which time it progresses forward about twelve inches, keeping the holes free of the pounded rock. The principal feature of the machine is that it imitates in every way the action of the quarryman in boring a rock. An-other type of rock-boring machine is the diamond drill, which surpasses all others in the rapidity with which it eats its way through solid rock.
Rock-boring is comparatively easy nowadays. When soft material is encountered the work is more difficult, it being necessary to keep the material from clogging the excavation already made. A device has been invented to overcome this, and it was used in the railroad tunnel under the St. Clair River at Port Huron. It is called a shield, and is generally used in cities for smaller tunnels. In the St. Clair tunnel a great cylinder weighing more than 6o tons, 20 feet in diameter, and 16 feet long, was driven into the blue clay, which constituted the entire bottom of the river, with as great ease as cakes of soap can be carved out of a general mass. Inside this "shield" twenty-two men worked removing the dirt. As fast as the shield was pushed forward, which was 2 feet at a time, the clay thus brought inside was dug out to the end of the cylinder. Then the hydraulic jacks were again started and slowly but irresistibly the immense iron tube moved another two feet into the solid earth ahead of it. Each jack had a power of 3,000 tons and the combined power behind the shield was more than 400,000 tons.
When water floods the work there is great risk. It was necessary to pump 2,000 gallons of water a minute to prevent the flooding of the Kilsby tunnel, and in the construction of the Severn tunnel in England (1873-85), which has a length of 4 1/3 miles, the tunnel was flooded for a year by the tapping of a large spring, and the erection of permanent pumping engines was made necessary.
The canals of the Century are not the greatest in length. There is one in China nearly 700 miles long, the longest in the world, that dates back to the Thirteenth Century. The era of canal opening in the United States began early, and the Erie canal running from Albany to Buffalo is 351.8 miles in length, and was opened in 1825. But these canal enterprises have been dwarfed as engineering enterprises and in importance by the Suez canal, which is regarded by many as the greatest engineering feat of the world. While the ancient Egyptians did not cut directly through the isthmus, Herodotus describes a canal from Suez to the Nile, but it became clogged with sand, and until DeLesseps dug his great ditch it was regarded as necessary for all ships to make the journey around Africa to reach the Indies. The isthmus made necessary a journey of 15,000 miles, and a glance at the map of Africa will show the enormous saving in time which it effects. The journey around Africa was so great that it was to avoid this that Columbus, ignorant of the size of the world, made his journey westward that led to the discovery of America.
The story of the canal is a thrilling romance. It was conceived by DeLesseps in 1834, twenty years before he got his concession. Then followed intrigues and diplomacy with Turkey and foreign powers before he could get permission to work. Then it became necessary to raise the enormous capital of $92,000,000 which it cost. In spite of the obstacles the objections were finally overcome and the canal built, being opened in November, 1869.
The Suez canal is 88 geographical or about T00 statute miles long. The engineering difficulties were enormous.
The minimum depth is 26 feet, and this was necessary because of the size of the vessels which would use it. Its average width is 25 yards. It had to be dug through sand, and it was made possible only by the invention of dredges to do the work. But for these the canal would never have been built through the sand. These dredges were the contrivance of one of the contractors. The use of the dredging machines was prepared for by digging out a rough trough by spade work and as soon as it had been dug to the depth of from six to twelve feet, the water was let in. After the water was let in the steam dredges were floated down the stream, moored against the bank and set to work. There were two kinds of dredges. One, known as couloir, was a large barge of wood supporting an endless chain of heavy iron buckets which scooped up the mud and sand which was discharged through pipes onto the embankment. Smaller movable dredges were also used which discharged the mud and sand on barges, which were divided into compartments fixed on trucks, and, raised by steam, were placed on an inclined plane that carried the mud to the shore. Many were the problems of engineering which were solved during the construction of the canal.
Another great canal is the one connecting the North Sea and the Baltic, running from the mouth of the Elbe to the gulf of Kiel. Begun in 1887, it was opened in 1895. It is 6o miles long and has a depth of 28 feet and a width of 197 feet, being sufficient to float the largest vessels of the German navy. The working plant consisted of ninety locomotives, 2,473 cars, 133 lighters, 55 steam-engines, and 8,600 men. The Manchester canal, which has made Manchester a seaport, is another great canal enterprise of the Century. Thirty-five and a half miles in length, it was opened in 1893, and has a depth of 26 feet and a width of 172 feet.
By the use of shields and dredges the engineers have sunk great piers, effected wonders in sanitary engineering, built sewers and jetties, using marvelous machinery, often invented expressly for the purpose. The levees built along the banks of the Mississippi and other rivers have been triumphs of engineering skill, and have saved thousands of lives from floods, although the loss of life is still great.
By the skill of the engineer, aided by the architect, tall buildings, rivaling the tower of Babel, rear their heads skyward in the great cities. Buildings of eighteen and twenty stories have ceased to be uncommon. They have been made necessary by the congestion of the great cities, for when from $150 to $300 a square foot is paid for land it is necessary to build tall structures in order to pay interest on the ground and the cost of the building. There was a limit beyond which structures of brick and wood might be built, but the use of iron and steel made it possible to build taller structures, two or three times the height of those possible by the old method The new method of construction known as the skeleton frame construction, does away with the use of brick and masonry except as a thin shell. Steel beams support the walls of each story and these are framed between columns, permitting thin walls even at the base. The frame work of iron and steel being erected, the masons and carpenters can work on all floors at once and build from top and bottom. Great as have been the improvements in construction, the erection of these buildings calls for the highest engineering skill. The Manhattan Life building in New York, which is twenty-three stories high, weighs 21,000 tons, and there is a pressure of wind estimated at 2,400 tons against its exposed sides, while the total weight, including tenants and furniture, is not far from 31,000 tons. It is necessary to so construct these buildings that the settling from the weight may be accurately estimated. A twenty-story structure will have sixteen elevators that will travel 120,000 miles in a year on 14 miles of wire ropes. From 30 to 50 miles of electrical wire serve to light the building and supply telephone connections for the two or three thousand people who live in the great edifices, while miles upon miles of steam pipes supply the tenants with water. In such buildings one may attend to every want without budging from them, there being post-office, express offices, telegraph offices, and other such conveniences, as well as restaurants and every kind of shop, except, perhaps, livery stables and feed-stores.
It is difficult to foretell the future of the construction of such buildings, but it is predicted that within a score of years they may reach thirty and forty stories in height.
Two of the most interesting pieces of engineering of the Century are the Eiffel tower and the Ferris wheel. The first, erected in 1889 as the crowning glory of the Paris Exposition and a triumph of French skill, was the idea of Gustave Eiffel. It is 985 feet high, contains 7,300 tons of iron, and cost $1,000,000. The appearance of the Eiffel tower is familiar to every one, and it is scarcely possible to convey any adequate idea of the great net-work of bracings by which each standard of the columns is united to form the loftiest structure in the world.
The engineering feat of the World's Columbian Ex-position held at Chicago was the Ferris wheel, the invention of G. W. G. Ferris, of Pittsburg. It is an enormous "merry-go-round," as the machine at country fairs is called, and the novelty consisted in its magnitude, which called for the highest engineering skill. The great wheel is 250 feet in diameter; and to its periphery were hung thirty-six carriages, each seating forty persons. At each revolution 1,440 people may be raised into the air and from that elevation afforded a splendid prospect, besides an experience of the peculiar sensation, like that of being in a balloon, when the spectator has no perception of his motion, but the objects beneath him appear to have the contrary motion; that is to say they seem to be sinking when he is rising and vice versa. Begun in March, 1893, the structure was completed in three months at a cost of $325,000.
Though the steam-engine itself is an invention of the previous Century, its application to everything under the sun is an achievement of the Nineteenth Century. The Century has also been remarkable for the attempts to get the greatest possible return from the fuel employed with the least possible waste, which followed the general recognition of the principle of the conservation of energy allusion to which is made in another part of this volume. The energy stored up in coal is converted into heat energy in the process of combustion, and transferred with various losses to steam. This is made by suitable engines to yield up some proportion of its heat energy for conversion into mechanical motion. More energy than the coal supplies it is impossible to obtain as energy of motion, and engineers with a clear realization of this principle have abandoned all schemes for the solution of the perpetual motion problem. The criticism of an engine is therefore on the returns which it yields for the expenditure of fuel. The inventions of the Century have been in the direction of the elimination of friction from the working parts and the employment of methods of construction that give greater power for a small total weight.
As Watt in the last Century found the steam engine an imperfect and wasteful arrangement for utilizing only a small portion of the energy of the steam supplied to it and by the invention of his condenser and then by making the engine double acting, made it really a steam engine; so a great step forward was taken by Woolf in 1804, when he developed the compound engine from the crude ideas of Hornblower of 1781. Using steam of fairly high pressure Woolf expanded it to several times its original volume by cutting off the supply before the end of the stroke in a small cylinder. Its chief advantage is that it limits to a great extent the waste which results from the heating and cooling of the metal by contact with hot and cooler steam. This is the greatest improvement in the steam engine since the time of Watt, but its advantage was not recognized until about the middle of the Century, when the discoveries of McNaught in 1845 and of Cowper in 1857, made possible the use of high-pressure steam, and compound expansion became more and more general. In marine engineering, where economy of fuel is of greatest importance, we find triple and even quadruple expansion engines, while the idea is recognized even in the locomotive engines of today. The 'first triple-expansion engine was made by Kirk in 1874.
In other directions the progress of the steam-engine has been in features of mechanical detail and its growing application to nearly every use.
The higher pressure of engines gave rise to a new problem, that of the strength of boiler, cylinders, and accessory connections necessary to withstand the enormous internal pressure of the steam. Improved quality of adaptability of iron and steel have made this possible, and steam boilers step by step have developed to their present form. Manual labor was used almost exclusively in this work until 1885, the boilers being of wrought iron and riveted by hand. Mild steel boiler plates and machine riveting have to a great extent succeeded these, although, in spite of the fact that hand-riveting is much slower, there are those who contend that it is better.
During the last few years the tubulous boiler has been introduced. This is made so that it has no large internal space and can thus be used for heat at high temperatures. It more nearly approaches the theory of Sadi-Carnot, evolved in 1824, which is that the efficiency of any heat engine has its maximum limit fixed by the range of temperature employed with the working substance.
Gas and petroleum engines have gained their development during this Century. Street's engine in 1794 was on the principle of internal combustion, to which they owe their origin, and was worked by the combustion of vaporized oil and turpentine. In engines of this type the working substance is heated by its own combustion in the motor cylinder, and because of the greater range of temperature employed they are of higher efficiency. The water jacket introduced by Brown in 1823, to keep the cylinder cool and prevent the rapid degradation due to heat, and the improvements of Lenoir have made them practicable. The Otto gas engine, introduced in 1863, was noisy and mechanically defective, but the Otto silent of 1876 has proved a powerful rival to small steam-engines. Air sufficient for combustion is mixed with gas and a temperature of about 1,600 centigrade, with a pressure of 100 pounds per square inch is obtained, with the expenditure of only twenty-four cubic feet of gas per horse power per hour. This is more economical than any small steam engine. But with larger engines the advantage is with the coal engine, except where natural gas is used. Gas is used in engines just as it is used in grates, stoves, and ranges, always on a comparatively small scale, where the high price is offset by cleanliness and convenience. A gas engine means only the turning on of a stop-cock and it comes to full speed in a minute or two and hence where small power is used or the large power is intermittent, the gas-engine is most economical.
Petroleum and gasoline engines, which have been successfully applied to horseless carriages, being the favorite method of propulsion for these vehicles work on the same principle as the gas engine. Instead of the simple admission of gas a sprayed jet of oil is broken up by compressed air playing on it in a nozzle. It is then further heated and fully vaporized by the hot products of the exhaust. The chief objection to the oil engine is its odor.
During the last half Century the improvements in steam-power have increased its use nearly fifty-fold. The growth of the use of steam has been from an effective horse power of 1,65o,000,000 tons horse power in 1840 to 9,850,000,000 in 1860 to 55,580,000,000 horse power in 1895, according to Mulhall's estimates. Of this total steam power, the United States and Great Britain together possess more than half that of the world, the horse power of the engines of the United States being 16,940,000,000 and that of the British engines 12,970,-000,000.
An interesting and important illustration of the economy in the application of steam-power to mechanical contrivances is the steam-hammer. Large forge hammers had been in use actuated by steam before Nasmyth's invention in 1842, but they were worked in an indirect manner, the hammer having been lifted by cams and other expedients, which rendered the apparatus cumbersome, costly, and wasteful of power on account of the indirect way in which the original source of the force namely, the pressure of steam had to reach its point of application by giving its blow to the hammer. The range of the fall of the hammer being only eighteen inches, there was a rapid decrease in the energy of blow in proportion to the size of the piece of iron. There was no means of controlling the force of the blow. Nasmyth hit upon the idea, when he received an order for the forging of a shaft for the paddle wheels of a steamer, the shaft to be three feet in diameter, a greater size than could be accommodated in any forge hammer in England. In a few minutes he hit upon the idea which has done more to revolutionize the manufacture of iron and steel than any other inventions that could be named, excepting those of Cort and Bessemer. For four years the hammer was not used outside of his shop, although now it is an absolute necessity in every engineering workshop. Owing to its vast range of power forged iron-work, by its means, can now be executed with a perfection not previously possible. Anything can be done with it, for the strength of the blow is regulated at will and the most minute details of machinery as well as the most gigantic parts are forged with its aid. At Woolwich arsenal there is a steam hammer, built in 1874, the falling portion of which weighs forty tons and which can strike a blow with a force of ninety-one tons.
The main feature of the steam-hammer is the direct manner by which the elastic power of steam is employed to lift up and let fall the mass of iron constituting the hammer, which is attached direct to the end of a piston-rod passing through the bottom of an inverted steam cylinder placed directly over the anvil. The steam is admitted below the piston, which is thus raised to any required height within the limits of the stroke. When the communication with the boiler is shut off and the steam below the piston is allowed to escape, the piston with the mass of iron forming the hammer _attached to the piston-rod falls by its own weight. This weight in large steam-hammers amounts to several tons, and the force of the blow will depend jointly upon the weight of the hammer and upon the height from which it is allowed to fall. The steam is admitted and allowed to escape by valves moved by a lever under the control of the work-man. By allowing the-hammer to be raised to a greater or less height, and by regulating the escape of the steam from beneath the piston, the operator has it in his power to vary the force of the blow. Men who are accustomed to this tool exhibit their perfect control with such ac-curacy that a watch may be placed face upwards on the anvil and a moistened wafer on it. The hammer will descend and pick up the wafer without cracking the crystal. Yet it may be a hammer capable of striking a blow of eighty tons.
Water-power has been used for thousands of years as a motive power, but its practical development has come within the last Century. The utilization of the vast forces has been greater, especially since water-power has been used as means for the furnishing of electricity, yet at the present time not 5 per cent of the water-power of the world has been rendered available for use, and the great Niagara Falls was not made to work until the last decade of the Nineteenth Century. While the modern turbine is the evolution of ages the principal developments were made during this century. J. Fourneyron in 1827 and St. Blasien in 1837 made great improvements, but in 1855 A. M. Swain, a mechanic who had been employed at the Lowell machine shop, conceived an idea which is the prototype of all the modern turbines; by combining the inward and downward flow wheels, curving the buckets both laterally and vertically he increased the efficiency of the water-wheel by 50 per cent. The gradual improvements since the time of Fourneyron in 1827 have served to furnish turbines of -equal power in one-half the space and at one-fifth the cost, an enormous economy of power. The cumbersome mechanism required to use the water of a high fall has been replaced by simple mechanism that makes use of a small fall. Of water as a means of the generation of electricity allusion will be made in the story of miscellaneous electrical achievements.