of the American Society of Civil Engineers, writes as follows on the subject of engineering, with special reference to American engineers and their works in the
Engineering is sometimes divided into civil, military, and naval engineering.
The logical classification is: statical engineering and dynamical.
Statical engineering can be again subdivided into structural engineering, or that of railways, bridges, tunnels, buildings, etc.; also, into hydraulic engineering, which governs the application of water to canals, river improvements, harbors, the supply of water to towns and for irrigation, disposal of sewage, etc.
Dynamical engineering can be divided into mechanical engineering, which covers the construction of all prime motors, the transmission of power, and the use of machines and machine tools.
Closely allied is electrical engineering, the art of
the transformation and transmission of energy for traction, lighting, telegraphy, telephoning, operating machinery, and many other uses, such as its electrolytic application to ores and metals.
Then we have the combined application of statical, mechanical, and electrical engineering to what is now called industrial engineering, or the production of articles useful to man. This may be divided into agricultural, mining, metallurgical, and chemical engineering.
This is the oldest of all. We have not been able to surpass the works of the past in grandeur or durability.
The pyramids of Egypt
still stand, and will stand for thousands of years.
Roman bridges, aqueducts, and sewers still perform their duties.
Joseph's canal still irrigates lower Egypt
The great wall of China
, running for 1,500 miles over mountains and plains, contains 150,000,000 cubic yards of materials and is the greatest of artificial works.
No modern building compares in grandeur with St. Peter
's, and the medieval cathedrals shame our puny imitations.
The greatest engineering work of the nineteenth century was the development of the railway system which has changed the face of the world.
Beginning in 1829 with the locomotive of George Stephenson
, it has extended with such strides that, after seventy years, there are 466,000 miles of railways in the world, of which 190,000 miles are in the United States
Their cost is estimated at $40,000,000,000, of which $10,000,000,000 belong to the United States
The rapidity with which railways are built in the United States
contrasts strongly with what has been done in other countries.
Much has been written of the energy of Russia
in building 3,000 miles of Siberian railway in five or six years. In the United States
an average of 6,147 miles was completed every year during ten successive years, and in 1887 there were built 12,982 miles. They were built economically, and at first in not as solid a manner as those of Europe
Steeper gradients, sharper curves, and lighter rails were used.
This rendered necessary a different kind of rolling-stock suitable to such construction.
The swivelling-truck and equalizing-beam enabled our engines to run safely on tracks where the rigid European
engines would soon have been in the ditch.
Our cars were made longer, and by the use of longitudinal framing much stronger.
A great economy came from the use of annealed cast-iron wheels.
It was soon seen that longer cars would carry a greater proportion of paying load, and the more cars that one engine could draw in a train, the less would be the cost.
It was not until the invention by Bessemer
in 1864 of a steel of quality and cost that made it available for rails that much heavier cars and locomotives could be used.
Then came a rapid increase.
As soon as Bessemer
rails were made in this country, the cost fell from $175 per ton to $50, and now to $26.
Before that time a wooden car weighed 16 tons, and could carry a paying load of 15 tons.
The 30-ton engines of those days could not draw on a level over thirty cars weighing 900 tons.
The pressed steel car of to-day weighs no more than the wooden car, but carries a paying load of 50 tons.
The heaviest engines have now drawn on a level fifty steel cars, weighing 3,750 tons.
In the one case the paying load of an engine was 450 tons; now it is 2,500 tons.
Steep grades soon developed a better brake system, and these heavier trains have led to the invention of the automatic brake worked from the engine, and also automatic couplers, saving time and many lives.
The capacity of our railways has been greatly increased by the use of electric block-signals.
The perfecting of both the railway and its rolling-stock has led to remarkable results.
In 1899 Poor gives the total freight tonnage at 975,789,941 tons, and the freight receipts at $922,436,314, or an average rate per ton of 95 cents. Had the rates of 1867 prevailed, the additional yearly cost to the public would have been $4,275,000,000, or sufficient to replace the whole railway system in two and a half years. This much can surely be said: the reduction in cost of operating our railways, and the consequent fall in freight rates, have been potent factors in enabling the United States
to send abroad last
year $1,456,000,000 worth of exports and flood the world with our food and manufactured products.
In early days the building of a bridge was a matter of great ceremony, and it was consecrated to protect it from evil spirits.
Its construction was controlled by priests, as the title of the Pope
, “Pontifex Maximus
Railways changed all this.
Instead of the picturesque stone bridge, whose long line of low arches harmonized with the landscape, there came the straight girder or high truss, ugly indeed, but quickly built, and costing much less.
Bridge construction has made greater progress in the United States
The heavy trains that we have described called for stronger bridges.
The large American
rolling-stock is not used in England
, and but little on the continent of Europe
, as the width of tunnels and other obstacles will not allow of it. It is said that there is an average of one bridge for every 3 miles of railway in the United States
, making 63,000 bridges, most of which have been replaced by new and stronger ones during the last twenty years. This demand has brought into existence many bridge-building companies, some of whom make the whole bridge, from the ore to the finished product.
Before the advent of railways, highway bridges in America
were made of wood, and called trusses.
The coming of railways required a stronger type of bridge to carry concentrated loads, and the Howe truss, with vertical iron rods, was invented, capable of 150-foot spans.
About 1868 iron bridges began to take the place of wooden bridges.
One of the first long-span bridges was a singletrack railway bridge of 400-foot span over the Ohio
, which was considered to be a great achievement in 1870.
The Kinzua viaduct, 310 feet high and over half a mile long, belongs to this era. It is the type of the numerous high viaducts now so common.
About 1885 a new material was given to engineers, having greater strength and tenacity than iron, and commercially available from its low cost.
This is basic steel.
This new chemical metal, for such it is, is 50 per cent. stronger than iron, and can be tied in a knot when cold.
The effect of improved devices and the use of steel is shown by the weights of the 400-foot Ohio River
iron bridge, built in 1870, and a bridge at the same place, built in 1886.
The bridge of 1870 was of iron, with a span of 400 feet. The bridge of 1886 was of steel.
Its span was 550 feet. The weights of the two were nearly alike.
The cantilever design, which is a revival of a very ancient type, came into use. The great Forth Bridge, in Scotland
, 1,600-foot span, is of this style, as are the 500-foot spans at Poughkeepsie
, and now a new one is being designed to cross the St. Lawrence
, of 1,800-foot span.
This is probably near the economic limit of cantilever construction.
The suspension bridge can be extended much farther, as it carries no dead weight of compression members.
The Niagara Suspension Bridge
, of 810-foot span, built by Roebling
, in 1852, and the Brooklyn Bridge
, of 1,600 feet, built by Roebling
and his son, twenty years after, marked a wonderful advance in bridge design.
The same lines of construction will be followed in the 2,700-foot span, designed to cross the North River
some time in the present century.
The only radical advance is the use of a better steel than could be had in earlier days.
Steel-arched bridges are now scientifically designed.
Such are the new Niagara Bridge, of 840-foot span, and the Alexandra Bridge
That which marks more clearly than anything else the great advance in American bridge building, during the last forty years, is the reconstruction of the famous Victoria Bridge, over the St. Lawrence
, above Montreal
This bridge was designed by Robert Stephenson
, and the stone piers are a monument to his engineering skill.
For forty winters they have resisted the great fields of ice borne by a rapid current.
Their dimensions were so liberal that the new bridge was put upon them, although four times as wide as the old one.
The superstructure was originally made of plate-iron tubes, reinforced by tees and
angles, similar to Stephenson's Menai Straits Bridge.
There are twenty-two spans of 240 feet each, and a central one of 330 feet.
It was decided to build a new bridge of open-work construction and of open-hearth steel.
This was done, and the comparison is as follows: Old bridge
, 16 feet wide, single track, live load of one ton per foot; new bridge, 67 feet wide, two railway tracks and two carriage-ways, live load of 5 tons per foot.
The old iron tubes weighed 10,000 tons, cost $2,713,000, and took two seasons to erect.
The new truss bridge weighs 22,000 tons, has cost $1,400,000, and the time of construction was one year.
The modern high office building is an interesting example of the evolution of a high-viaduct pier.
Such a pier of the required dimensions, strengthened by more columns strong enough to carry many floors, is the skeleton frame.
Enclose the sides with brick, stone, or terra-cotta, add windows, and doors, and elevators, and it is complete.
Fortunately for the stability of these high buildings, the effect of wind pressures had been studied in this country in the designs of the Kinzua, Pecos
, and other high viaducts.
The modern elevated railway of cities is simply a very long railway viaduct.
Some idea may be gained of the life of a modern riveted-iron structure from the experience of the Manhattan Elevated Railway
of New York.
These roads were built in 1878-79 to carry uniform loads of 1,600 lbs. per lineal foot, except Second Avenue, which was made to carry 2,000.
The stresses were below 10,000 lbs. Per square inch.
These viaducts have carried in twenty-two years over 25,000,000 trains, weighing over 3,000,000,000 tons, at a maximum speed of 25 miles an hour, and are still in good order.
We have now great bridge companies, which are so completely equipped with appliances for both shop drawings and construction that the old joke becomes almost true that they can make bridges and sell them by the mile.
All improvements of design are now publie property.
All that the bridge companies do is done in the fierce light of competition.
Mistakes mean ruin, and the fittest only survives.
The American system gives the greatest possible rapidity of erection of the bridge on its piers.
A span of 518 feet, weighing 1,000 tons, was erected at Cairo
on the Mississippi
in six days. The parts were not assembled until they were put upon the false works.
engineers have sometimes ordered a bridge to be riveted together complete in the maker's yard, and then taken apart.
The adoption of American work in such bridges as the Atbara in South Africa
, the Gokteik viaduct in Burmah
, 320 feet high, and others, was due to low cost, quick delivery and erection, as well as excellence of material and construction.
Bridges must have foundations for their piers.
Up to the middle of the nineteenth century engineers knew no better way of making them than by laying bare the bed of the river by a pumped-out cofferdam, or by driving piles into the sand, as Julius Caesar
did. About the middle of the century, M. Triger
, a French engineer, conceived the first plan of a pneumatic foundation, which led to the present system of compressing air by pumping it into an inverted box, called a caisson, with air locks on top to enable men and materials to go in and out. After the soft materials were removed, and the caisson sunk by its own weight to the proper depth, it was filled with concrete.
The limit of depth is that in which men can work in compressed air without injury, and this is not much over 100 feet.
The foundations of the Brooklyn
and St. Louis bridges were put down in this manner.
In the construction of the Poughkeepsie bridge
over the Hudson
in 1887-88, it became necessary to go down 135 feet below tide-level before hard bottom was reached.
Another process was invented to take the place of compressed air. Timber caissons were built, having double sides, and the spaces between them filled with stone to give weight.
Their tops were left open and the American
singlebucket dredge was used.
This bucket was lowered and lifted by a very long wire rope worked by the engine, and with it the soft material was removed.
internal space was then filled with concrete laid under water by the same bucket, and levelled by divers when necessary.
While this work was going on, the government of New South Wales, in Australia
, called for both designs and tenders for a bridge over an estuary of the sea called Hawkesbury.
The conditions were the same as that at Poughkeepsie
, except that the soft mud reached to a depth of 160 feet below tide-level.
The designs of the engineers of the Poughkeepsie bridge
were accepted, and the same method of sinking open caissons (in this case made of iron) was carried out with perfect success.
The erection of this bridge involved another difficult problem.
The mud was too soft and deep for piles and staging, and the cantilever system in this site would have increased the cost.
The solution of the problems presented at Hawkesbury gave the second introduction of American engineers to bridge building outside of America
The first was in 1786, when an American carpenter or shipwright built a bridge over Charles River
, 1,470 feet long by 46 feet wide.
This bridge was of wood supported on piles.
His work gained for him such renown that he was called to Ireland
and built a similar bridge at Belfast
Tunnelling by compressed air is a horizontal application of compressed-air foundations.
The earth is supported by an iron tube, which is added to in rings, which are pushed forward by hydraulic jacks.
A tunnel is now being made under an arm of the sea between Boston
and East Boston
, some 1,400 feet long and 65 feet below tide.
The interior lining of iron tubing is not used.
The tunnel is built of concrete, reinforced by steel rods.
Success in modern engineering means doing a thing in the most economical way consistent with safety.
Had the North River
tunnel, at New York, been designed on equally scientific principles it would probably have been finished, which now seems problematical.
The construction of rapid-transit railways in cities is another branch of engineering.
Some of these railways are elevated, and are merely railway viaducts, but the favorite type now is that of subways.
There are two kinds, those near the surface, like the District
railways of London
, the subways in Paris
, and Boston
, and that now building in New York.
The South London
and Central London
, and other London
projects, are tubes sunk 50 to 80 feet below the surface and requiring elevators for access.
The construction of the Boston
subway was difficult on account of the small width of the streets, their great traffic, and the necessity of underpinning the foundations of buildings.
All of this was successfully done without disturbing the traffic for a single day, and reflects great credit on the engineer.
Owing to the great width of New York streets, the problem is simpler in that respect.
Although many times as long as the Boston
subway, it will be built in nearly the same time.
The design, where in earth, may be compared to that of a steel office building 20 miles long, laid flat on one of its sides.
The construction of power-houses for developing energy from coal and from falling water requires much engineering ability.
power-house is intended to develop 100,000 horse-power; that at the Sault Ste. Marie
as much; that on the St. Lawrence
, at Massena
, 70,000 horse-power. These are huge works, requiring tunnels, rock-cut chambers, and masonry and concrete in walls and dams.
They cover large extents of territory.
The contrast in size of the coal-using power-houses is interesting.
The new power-house now building by the Manhattan Elevated Railway
, in New York, develops in the small space of 200 by 400 feet 100,000 horse-power, or as much power as that utilized at Niagara Falls
One of the most useful materials which modern engineers now make use of is concrete, which can be put into confined spaces and laid under water.
It costs less than masonry, while as strong.
This is the revival of the use of a material used by the Romans.
The writer was once allowed to climb a ladder and look at the construction of the dome of the Pantheon, at Rome
He found it a monolithic mass of concrete, and hence without thrust.
It is a better piece of engineering construction than the dome of St. Peter
1,500 years later.
The dome of Columbia College Library, in New York, is built of concrete.
This is one of the oldest branches of engineering, and was developed before the last century.
The irrigation works of Asia
, the Roman
aqueducts, and the canals of Europe
, are examples.
Hydraulic works cannot be constructed in ignorance of the laws which govern the flow of water.
The action of water is relentless, as ruined canals, obstructed rivers, and washed-out dams testify.
The removal of sewage, after having been done by the Etruscans before the foundation of Rome
, became a lost art during the dirty Dark Ages, when filth and piety were deemed to be connected in some mysterious way. It was reserved for good John Wesley
to point out that “Cleanliness is next to godliness.”
Now sewage works are as common as those for water supply.
Some of them have been of great size and cost.
Such are the drainage works of London
, and New Orleans.
A very difficult work was the drainage of the City of Mexico
, which is in a valley surrounded by mountains, and elevated only 4 or 5 feet above a lake having no outlet.
Attempts to drain the lake had been made in vain for 600 years. It has lately been accomplished by a tunnel 6 miles long through the mountains, and a canal of over 30 miles, the whole work costing some $20,000,000.
The drainage of Chicago
by locks and canal into the Illinois River
has cost some $35,000,000, and is well worth its cost.
Scientific research has been applied to the designing of high masonry and concrete dams, and we know now that no well-designed dam on a good foundation should fail.
The dams now building across the Nile
by order of the British
government will create the largest artificial lakes in the world.
The Suez Canal
is one of the largest hydraulic works of the last century, and is a notable instance of the displacement of hand labor by the use of machinery.
Ismail began by impressing a large part of the peasant population of Egypt
, just as Rameses had done over 3,000 years before.
These unfortunate people were set to dig the sand with rude hoes, and carry it away in baskets on their heads.
They died by thousands for want of water and proper food.
At last the French
engineers persuaded the Khedive to let them introduce steam dredging machinery.
A light railway was laid to supply provisions, and a small ditch dug to bring pure water.
The number of men employed fell to one-fourth.
Machinery did the rest.
But for this the canal would never have been finished.
The Panama Canal
now uses the best modern machinery, and the Nicaragua Canal
, if built, will apply still better methods, developed on the Chicago
drainage canal, where material was handled at a less cost than has ever been done before.
The Erie Canal
was one of very small cost, but its influence has been surpassed by none.
The “winning of the West
” was hastened many years by the construction of this work in the first quarter of the century.
Two horses were just able to draw a ton of goods at the speed of 2 miles an hour over the wretched roads of those days.
When the canal was made these two horses could draw a boat carrying 150 tons 4 miles an hour.
The Erie Canal
was made by engineers, but it had to make its own engineers first, as there were none available in this country at that time.
These self-taught men, some of them land surveyors and others lawyers, showed themselves the equals of the Englishmen Brindley
, when they located a water route through the wilderness, having a uniform descent from Lake Erie
to the Hudson
, and which would have been so built if there had been enough money.
There should be a waterway from the Hudson
to Lake Erie
large enough for vessels able to navigate the lakes and the ocean.
A draft of 21 feet can be had at a cost estimated at $200,000,000.
The deepening of the Chicago
drainage canal to the Mississippi River
, and the deepening of the Mississippi
itself to the Gulf of Mexico
, is a logical sequence of the first project.
The Nicaragua Canal
would then form one part of a great line of navigation, by which the products of the interior of the continent could reach either the Atlantic
or Pacific Ocean
The cost would be small compared with the resulting benefits, and some day this navigation will be built by the government of the United States
The deepening of the Southwest
Pass of the Mississippi River
from 6 to 30 feet by James B. Eads
was a great engineering achievement.
It was the first application of the jetty system on a large scale.
This is merely confining the flow of a river, and thus increasing its velocity so that it secures a deeper channel for itself.
The improvement of harbors follows closely the increased size of ocean and lake vessels.
The approach to New York Harbor is now being deepened to 40 feet, a thing impossible to be done without the largest application of steam machinery in a suction dredge boat.
The Croton Aqueduct of New York was thought by its designers to be on a scale large enough to last for all time.
It is now less than sixty years old, and the population of New York will soon be too large to be supplied by it. It is able to supply 250,000,000 to 300,000,000 galions daily, and its cost, when the Cornell dam
and Jerome Park
reservoir are finished, will be a little over $92,000,000.
It is now suggested to store water in the Adirondack Mountains
, 203 miles away, by dams built at the outlet of ten or twelve lakes.
This will equalize the flow of the Hudson River
so as to give 3,000,000,000 to 4,000,000,000 gallons daily.
It is then proposed to pump 1,000,000,000 gallons daily from the Hudson River
, 60 miles away, to a height sufficient to supply New York City by gravity through an aqueduct.
If this scheme is carried out, the total supply will be about 1,300,000,000 gallons daily, or enough for a population of from 12,000,000 to 13,000,000 persons.
By putting in more pumps, filter-beds, and conduits, this supply can be increased 40 per cent., or to 1,800,000,000 gallons daily.
This is a fair example of the scale of the engineering works of the nineteenth and twentieth centuries.
This is employed in all dynamical engineering.
It covers the designs of prime motors of all sorts, steam, gas, and gasoline reciprocating engines; also steam and water turbines, wind-mills, and wave-motors.
It comprises all means of transmitting power, as by shafting, ropes, pneumatic pressure, and compressed air, all of which seem likely to be superseded by electricity.
It covers the construction of machine tools and machinery of all kinds.
It enters into all the processes of structural.
hydraulic, electrical, and industrial engineering.
The special improvements are: The almost universal use of rotary motion, and of the reduplication of parts.
The steam-engine is a machine of reciprocating, converted into rotary, motion by the crank.
The progress of mechanical engineering during the nineteenth century is measured by the improvements of the steam-engine, principally in the direction of saving fuel, by the invention of internal combustion or gas-engines, the application of electrical transmission, and, latest, the practical development of steam turbines by Parsons
, Delaval, Curtis
, and others.
In these a jet of steam impinges upon buckets set upon the circumference of a wheel.
Their advantages are that their motion is rotary and not reciprocal.
They can develop speed of from 5,000 to 30,000 revolutions per minute, while the highest ever attained by a reciprocating engine is not over 1,000.
Their thermodynamic losses are less, hence they consume less steam and less fuel.
Duplication of parts has lowered the cost of all products.
Clothing is one of these.
The parts of ready-made garments.
and shoes are now cut into shape in numbers at a time, by sharp-edged templates, and then fastened together by sewingmachines.
Mechanical engineering is a good example of the survival of the fittest.
Millions of dollars are expended on machinery, when suddenly a new discovery or invention casts them all into the scrap heap, to be replaced by those of greater earning capacity.
Prime motors derive their energy either from coal or other combinations of carbon, such as petroleum, or from gravity.
This may come from falling water, and the old-fashioned water-wheels of the eighteenth century were superseded in the nineteenth by turbines, first invented in France
and since greatly perfected.
are used in the electrical transmission of water-power at Niagara
of 5,000 horsepower, and form a very important part of the plant.
The other gravity motors are windmills and wave-motors.
Wind-mills are an old invention, but have been greatly improved in the United States
by the use of the self-reefing wheel.
The great plains of the West
are subject to sudden, violent gales of wind, and unless the wheel was automatically self-reefing it would often be destroyed.
There have been vast numbers of patents taken out for wave-motors.
One was invented in Chile, South America
, which furnished a constant power for four months, and was utilized in sawing planks.
The action of waves is more constant on the Pacific coast
than elsewhere, and some auxiliary power, such as a gasoline engine, which can be quickly started and stopped, must be provided for use during calm days.
The prime cost of such a machine need not exceed that of a steam plant, and the cost of operating is much less than that of any fuelburning engine.
The saving of coal is a very important problem.
In a wider sense, we may say that the saving of all the great stores which nature has laid up for us during the past, and which have remained almost untouched until the nineteenth century, is the
great problem of to-day.
Petroleum and natural gas may disappear.
The ores of gold
, and platinum will not last forever.
Trees will grow, and iron ores seem to be practically inexhaustible.
Chemistry has added a new metal in aluminum, which replaces copper for many purposes.
One of the greatest problems of the twentieth century is to discover some chemical process for treating iron, by which oxidation will not take place.
Coal, next to grain, is the most important of nature's gifts; it can be exhausted, or the cost of mining it become so great that it cannot be obtained in the countries where it is most needed; water, wind, and wave power may take its place to a limited extent, and greater use may be made of the waste gases coming from blast or smelter furnaces, but as nearly all energy comes from coal, its use must be economized, and the greatest economy will come from pulverizing coal and using it in the shape of a fine powder.
Inventions have been made trying to deliver this powder into the fire-box as fast as made, for it is as explosive as gunpowder, and as dangerous to store or handle.
If this can be done, there will be a saving of coal due to perfect and smokeless combustion, as the admission of air can be entirely regulated, the same blast which throws in the powder furnishing oxygen.
Some investigators have estimated that the saving of coal will be as great as 20 per cent. This means 100,000,000 tons of coal annually.
Another problem of mechanical engineering is to determine whether it will be found more economical to transform the energy of coal, at the mines, into electric current and send it by wire to cities and other places where it is wanted, or to carry the coal by rail and water, as we now do, to such places, and convert it there by the steam or gas engine.
Metallurgy and mining.
All the processes of metallurgy and mining employ statical, hydraulic, mechanical, and electrical engineering.
Coal, without railways and canals, would be of little use, unless electrical engineering came to its aid.
It was estimated by the late Lord Armstrong that of the 450,000,000 to 500,000,000 tons of coal annually produced in the world, one-third is used for steam production, one-third in metallurgical processes, and one-third for domestic consumption.
Next in importance comes the production of iron and steel.
Steel, on account of its great cost and brittleness, was only used for tools and special purposes until past the middle of the nineteenth century.
This has been all changed by the invention of his steel by Bessemer
in 1864, and open-hearth steel in the furnace of Siemens
, perfected some twenty years since by Gilchrist
The United States
have taken the lead in steel manufacture.
In 1873 Great Britain
made three times as much steel as the United States
Now the United States
makes twice as much as Great Britain
, or 40 per cent. of all the steel made in the world.
has explained the reason why, in epigrammatic phrase: “Three
lbs. of steel billets can be sold for 2 cents.”
This stimulates rail and water traffic and other industries, as he tells us 1 lb. of steel requires 2 lbs. of ore, 1 1/3 lbs. of coal, and 1/3 lb. of limestone.
It is not surprising, therefore, that the States bordering on the lakes have created a traffic of 25,000,000 tons yearly through the Sault Ste
. Marie Canal, while the Suez, which supplies the wants of half the population of the world, has only 7,000,000, or less than the tonnage of the little Harlem River
at New York.
This leads us to our last topic, for which too little room has been left.
Industrial engineering covers statical, hydraulic, mechanical, and electrical engineering, and adds a new branch which we may call chemical engineering.
This is pre-eminently a child of the nineteenth century, and is the conversion of one thing into another by a knowledge of their chemical constituents.
first applied mathematics to chemistry and made it quantitative, he gave the key which led to the discoveries of Cavendish
, Berzelius, Liebig
, and others.
This new knowledge was not locked up, but at once given to the world, and made use of. Its first application on a large scale was made by Napoleon in encouraging the manufacture of sugar from beets.
The new products were generally made from what were called “waste material.”
We now have the manufacture of soda, bleaching powders, aniline dyes, and other products of the distillation of coal, also coal-oil
from petroleum, acetylene gas, celluloid, rubber goods in all their numerous varieties, high explosives, cement, artificial manures, artificial ice, beet-sugar, and even beer may now be included.
The value of our mechanical and chemical products is great, but it is surpassed by that of food products.
If these did not keep pace with the increase of population, the theories of Malthus
would be true—but he never saw a modern reaper.
The steam-plough was invented in England
some fifty years since, but the great use of agricultural machinery dates from our Civil War, when so many men were taken from agriculture.
It became necessary to fill their places with machinery.
Without tracing the steps which have led to it, we may say that the common type is what is called “the binder,” and is a machine drawn chiefly by animals, and in some cases by a field locomotive.
It cuts, rakes, and binds sheaves of grain at one operation.
Sometimes threshing and winnowing machines are combined with it, and the grain is delivered into bags ready for the market.
Different machines are used for cutting and binding corn, and for mowing and raking hay, but the most important of all is the grain-binder.
The extent of their use may be known from the fact that 75,000 tons of twine are used by these machines annually.
It is estimated that there are in the United States
1,500,000 of these machines, but as the harvest is earlier in the South
, there are probably not over 1,000,000 in use at one time.
As each machine takes the place of sixteen men, this means that 16,000,000 men are released from farming for other pursuits.
It is fair to assume that a large part of these 16,000,000 men have gone into manufacturing, the operating of railways, and other pursuits.
The use of agricultural machinery, therefore, is one explanation of why the United States
produces eight-tenths of the world's cotton and corn.
one-quarter of its wheat, one-third of its meat and iron, two-fifths of its steel, and one-third of its coal, and a large part of the world's manufactured goods.
It is a very interesting question, why was this great development of material prosperity delayed so late?
Why did it wait until the nineteenth century, and then all at once increase with such rapid strides?
It was not until modern times that the reign of law was greatly extended, and men were insured the product of their labors.
Then came the union of scientists, inventors, and engineers.
So long as these three classes worked separately but little was done.
There was an antagonism between them.
Ancient writers went so far as to say that the invention of the arch and of the potter's wheel were beneath the dignity of a philosopher.
One of the first great men to take a different view was Francis Bacon
, in his famous essay, quotes him as saying: “Philosophy is the relief of man's estate, and the endowment of the human race with new powers; increasing their pleasures and mitigating their sufferings.”
These noble words seem to anticipate the famous definition of civil engineering, embodied by Telford
in the charter of the British Institution of Civil Engineers: “Engineering is the art of controlling the great powers of nature for the use and convenience of man.”
The seed sown by Bacon
was long in producing fruit.
Until the laws of nature were better known, there could be no practical application of them.
Towards the end of the eighteenth century a great intellectual revival took place.
In literature appeared Voltaire
, and Goethe
In pure science there came Laplace
, Lavoisier, Linnaeus
, Berzelius, Priestley
, Count Rumford
, James Watt
, and Dr. Franklin
The last three were among the earliest to bring about a union of pure and applied science.
immediately applied his discovery that frictional electricity and lightning were the same to the protection of buildings by lightning-rods.
(whose experiments on the conversion of power into heat led to the discovery of the conservatism of energy) spent a long life in contriving useful inventions.
, one of the few men who have united in themselves knowledge of abstract science, great inventive faculties, and rare mechanical skill, changed the steam-engine from a worthless rattletrap into the most useful machine ever invented by man. To do this he first discovered the science of thermodynamics, then invented the necessary appliances, and finally constructed them with his own hands.
He was a very exceptional man. At the beginning of the nineteenth century there were few engineers who had received any scientific education.
Now there is in the profession a great army of young men, most of them graduates of technical schools, good mathematicians, and well versed in the art of experimenting.
One of the present causes of progress is that all discoveries are published at once in technical journals and in the daily press.
The publication of descriptive indexes of all scientific and engineering articles as fast as they appear is another modern contrivance.
Formerly scientific discoveries were concealed by cryptograms, printed in a dead language, and hidden in the archives of learned societies.
Even so late as 1821 Oersted published his discovery of the uniformity of electricity and magnetism in Latin.
Engineering works could have been designed and useful inventions made, but they could not have been carried out without combination.
Corporate organization collects the small savings of many into great sums through savings-banks, life insurance
companies, etc., and uses this concentrated capital to construct the vast works of our days.
This could not continue unless fair dividends were paid.
Everything now has to be designed so as to pay. Time, labor, and material must be saved, and he ranks highest who can best do this.
Invention has been encouraged by liberal patent laws, which secure to the inventor property in his ideas at a moderate cost.
Combination, organization, and scientific discovery, inventive ability, and engineering skill are now united.
It may be said that we have gathered together all the inventions of the nineteenth century and called them works of engineering.
This is not so. Engineering covers much more than invention.
It includes all works of sufficient size and intricacy to require men trained in the knowledge of the physical conditions which govern the mechanical application of the laws of nature.
First comes scientific discovery, then invention, and lastly engineering.
and Henry discovered the electrical laws which led to the invention of the dynamo, which was perfected by many minds.
Engineering built such works as those at Niagara Falls
to make it useful.
An ignorant man may invent a safetypin, but he cannot build the Brooklyn Bridge
The engineer-in-chief commands an army of experts, as without specialization little can be done.
His is the comprehensive design, for which he alone is responsible.
Such is the evolution of engineering,
which began as a craft and has ended as a profession.
Thoughtful persons have asked, will this new civilization last, or will it go the way of its predecessors?
Surely the answer is: all depends on good government, on the stability of law, order, and justice, protecting the rights of all classes.
It will continue to grow with the growth of good government, prosper with its prosperity, and perish with its decay.