ELECTRIC POWER.
On the discovery of electromagnetism (Chap. IV.), Faraday, Barlow,
and others devised experimental apparatus for producing rotary
motion from the electric current, and in 1831, Joseph Henry, the
famous American electrician, invented a small electromagnetic
engine or motor. These early machines were actuated by the current
from a voltaic battery, but in the middle of the century Jacobi
found that a dynamo-electric generator can also work as a motor,
and that by coupling two dynamos in circuit--one as a generator,
the other as a motor--it was possible to transmit mechanical power
to any distance by means of electricity. Figure 76 is a diagram of
a simple circuit for the transmission of power, where D is the
technical symbol for a dynamo as a generator, having its poles (+
and -) connected by wire to the poles of M, the distant dynamo, as
a motor. The generator D is driven by mechanical energy from any
convenient source, and transforms it into electric energy, which
flows through the circuit in the direction of the arrows, and, in
traversing the motor M, is re-transformed into mechanical energy.
There is, of course, a certain waste of energy in the process, but
with good machines and conductors, it is not more than 10 to 25
per cent., or the "efficiency" of the installation is from 75 to
90 per cent--that is to say, for every 100 horse-power put into
the generator, from 75 to 90 horse-power are given out again by
the motor.
It was not until 1870, when Gramme had improved the dynamo, that
power was practically transmitted in this way, and applied to
pumping water, and other work. Since then great progress has been
made, and electricity is now recognised, not only as a rival of
steam, but as the best means of distributing steam, wind, water,
or any other power to a distance, and bringing it to bear on the
proper point.
The first electric railway, or, rather, tramway, was built by Dr.
Werner von Siemens at Berlin in 1879, and was soon followed by
many others. The wheels of the car were driven by an electric
motor drawing its electricity from the rails, which were insulated
from the ground, and being connected to the generator, served as
conductors. It was found very difficult to insulate the rails, and
keep the electricity from leaking to the ground, however, and at
the Pans Electrical Exhibition of 1881, von Siemens made a short
tramway in which the current was drawn from a bare copper
conductor running on poles, like a telegraph wire, along the line.
The system will be understood from figure 77, where L is the
overhead conductor joined to the positive pole of the dynamo or
generator in the power house, and C is a rolling contact or
trolley wheel travelling with the car and connected by the wire W
to an electric motor M under the car, and geared to the axles.
After passing through the motor the current escapes to the rail R
by a brush or sliding contact C', and so returns to the negative
pole of the generator. A very general way is to allow the return
current to escape to the rails through the wheels. Many tramways,
covering thousands of miles, are now worked on this plan in the
United States. At Bangor, Maine, a modification of it is in use
whereby the conductor is divided into sections, alternately
connected to the positive and negative poles of two generators,
coupled together as in the "three-wire system" of electric
lighting (page 119), their middle poles being joined to the earth
--that is to say, the rails. It enables two cars to be run on the
same line at once, and with a considerable saving of copper.
To make the car independent of the conductor L for a short time,
as in switching, a battery of accumulators B may be added and
charged from the conductor, so that when the motor is disconnected
from the conductor, the discharge from the accumulator may still
work it and drive the wheels.
Attempts have been made to run tramcars with the electricity
supplied by accumulators alone, but the system is not economical
owing to the dead weight of the cells, and the periodical trouble
of recharging them at the generating station.
On heavy railroads worked by electricity the overhead conductor is
replaced by a third rail along the middle of the track, and
insulated from the ground In another system the middle conductor
is buried underground, and the current is tapped at intervals by
the motor connecting with it for a moment by means of spring
contacts as the car travels In each case, however, the outer rails
serve as the return conductors
Another system puts one or both the conductors in a conduit
underground, the trolley pole entering through a narrow slot
similar to that used on cable roads
The first electric carriages for ordinary roads were constructed
in 1889 by Mr. Magnus Volk of Brighton. Figure 78 represents one
of these made for the Sultan of Turkey, and propelled by a one-
horse-power Immisch electric motor, geared to one of the hind
wheels by means of a chain. The current for the motor was supplied
by thirty "EPS" accumulators stowed in the body of the vehicle,
and of sufficient power to give a speed of ten miles an hour. The
driver steers with a hand lever as shown, and controls the speed
by a switch in front of him.
Vans, bath chairs, and tricycles are also driven by electric
motors, but the weight of the battery is a drawback to their use.
In or about the year 1839, Jacobi sailed an electric boat on the
Neva, with the help of an electromagnetic engine of one horse-
power, fed by the current from a battery of Grove cells, and in
1882 a screw launch, carrying several passengers, and propelled by
an electric motor of three horse-power, worked by forty-five
accumulators, was tried on the Thames. Being silent and smokeless
in its action, the electric boat soon came into favour, and there
is now quite a flotilla on the river, with power stations for
charging the accumulators at various points along the banks.
Figure 79 illustrates the interior of a handsome electric launch,
the Lady Cooper, built for the "E P S," or Electric Power Storage
Company. An electric motor in the after part of the hull is
coupled directly to the shaft of the screw propeller, and fed by
"E P S" accumulators in teak boxes lodged under the deck
amidships. The screw is controlled by a switch, and the rudder by
an ordinary helm. The cabin is seven feet long, and lighted by
electric lamps. Alarm signals are given by an electric gong, and a
search-light can be brought into operation whenever it is
desirable. The speed attained by the Lady Cooper is from ten to
fifteen knots.
M. Goubet, a Frenchman, has constructed a submarine boat for
discharging torpedoes and exploring the sea bottom, which is
propelled by a screw and an electric motor fed by accumulators. It
can travel entirely under water, below the agitation of the waves,
where sea-sickness is impossible, and the inventor hopes that
vessels of the kind will yet carry passengers across the Channel.
The screw propeller of the Edison and Sim's torpedo is also driven
by an electric motor. In this case the current is conveyed from
the ship or fort which discharges the torpedo by an insulated
conductor running off a reel carried by the torpedo, the "earth"
or return half of the circuit being the sea-water.
All sorts of machinery are now worked by the electric motor--for
instance, cranes, elevators, capstans, rivetters, lathes, pumps,
chaff-cutters, and saws. Of domestic appliances, figure 80 shows
an air propeller or ventilation fan, where F is a screw-like fan
attached to the spindle of the motor M, and revolving with its
armature. Figure 81 represents a Trouve motor working a sewing-
machine, where N is the motor which gears with P the driving axle
of the machine. Figure 82 represents a fine drill actuated by a
Griscom motor. The motor M is suspended from a bracket A B C by
the tackle D E, and transmits the rotation of its armature by a
flexible shaft S T to the terminal drill O, which can be applied
at any point, and is useful in boring teeth.
Now that electricity is manufactured and distributed in towns and
villages for the electric light, it is more and more employed for
driving the lighter machinery. Steam, however, is more economical
on a large scale, and still continues to be used in great
factories for the heavier machinery. Nevertheless a day is coming
when coal, instead of being carried by rail to distant works and
cities, will be burned at the pit mouth, and its heat transformed
by means of engines and dynamos into electricity for distribution
to the surrounding country. I have shown elsewhere that peat can
be utilised in a similar manner, and how the great Bog of Allen is
virtually a neglected gold field in the heart of Ireland.
[Footnote: The Nineteenth Century for December 1894.] The sunshine
of deserts, and perhaps the electricity of the atmosphere, but at
all events the power of winds, waves, and waterfalls are also
destined to whirl the dynamo, and yield us light, heat, or motion.
Much has already been done in this direction. In 1891 the power of
turbines driven by the Falls of Neckar at Lauffen was transformed
into electricity, and transmitted by a small wire to the
Electrical Exhibition of Frankfort-on-the-Main, 117 miles away.
The city of Rome is now lighted from the Falls of Tivoli, 16 miles
distant. The finest cataract in Great Britain, the Falls of
Foyers, in the Highlands, which persons of taste and culture
wished to preserve for the nation, is being sacrificed to the
spirit of trade, and deprived of its waters for the purpose of
generating electricity to reduce aluminium from its ores.
The great scheme recently completed for utilizing the power of
Niagara Falls by means of electricity is a triumph of human
enterprise which outrivals some of the bold creations of Jules
Verne.
When in 1678 the French missionaries La Salle and Hennepin
discovered the stupendous cataract on the Niagara River between
Lake Ontario and Lake Erie, the science of electricity was in its
early infancy, and little more was known about the mysterious
force which is performing miracles in our day than its
manifestation on rubbed amber, sealing-wax, glass, and other
bodies. Nearly a hundred years had still to pass ere Franklin
should demonstrate the identity of the electric fire with
lightning, and nearly another hundred before Faraday should reveal
a mode of generating it from mechanical power. Assuredly, neither
La Salle nor his contemporaries ever dreamed of a time when the
water-power of the Falls would be distributed by means of
electricity to produce light or heat and serve all manner of
industries in the surrounding district. The awestruck Iroquois
Indians had named the cataract "Oniagahra," or Thunder of the
Waters, and believed it the dwelling-place of the Spirit of
Thunder. This poetical name is none the less appropriate now that
the modern electrician is preparing to draw his lightnings from
its waters and compel the genius loci to become his willing
bondsman.
The Falls of Niagara are situated about twenty-one miles from Lake
Erie, and fourteen miles from Lake Ontario. At this point the
Niagara River, nearly a mile broad, flowing between level banks,
and parted by several islands, is suddenly shot over a precipice
170 feet high, and making a sharp bend to the north, pursues its
course through a narrow gorge towards Lake Ontario. The Falls are
divided at the brink by Goat Island, whose primeval woods are
still thriving in their spray. The Horseshoe Fall on the Canadian
side is 812 yards, and the American Falls on the south side are
325 yards wide. For a considerable distance both above and below
the Falls the river is turbulent with rapids.
The water-power of the cataract has been employed from olden
times. The French fur-traders placed a mill beside the upper
rapids, and the early British settlers built another to saw the
timher used in their stockades. By-and-by, the Stedman and Porter
mills were established below the Falls; and subsequently, others
which derived their water-supply from the lower rapids by means of
raceways or leads. Eventually, an open hydraulic canal, three-
fourths of a mile long, was cut across the elbow of land on the
American side, through the town of Niagara Falls, between the
rapids above and the verge of the chasm below the Falls, where,
since 1874, a cluster of factories has arisen, which discharge
their spent water over the cliff in a series of cascades almost
rivalling Niagara itself. This canal, which only taps a mere drop
from the ocean of power that is running to waste, has been
utilised to the full; and the decrease of water-privileges in the
New England States, owing to the clearing of the forests and
settlement of the country, together with the growth of the
electrical industries, have led to a further demand on the
resources of Niagara.
With the example of Minneapolis, which draws the power for its
many mills from the Falls of St. Anthony, in the Mississippi
River, before them, a group of far-seeing and enterprising
citizens of Niagara Falls resolved to satisfy this requirement by
the foundation of an industrial city in the neighbourhood of the
Falls. They perceived that a better site could nowhere be found on
the American Continent. Apart from its healthy air and attractive
scenery, Niagara is a kind of half-way house between the East and
West, the consuming and the producing States. By the Erie Canal at
Tonawanda it commands the great waterway of the Lakes and the St.
Lawrence. A system of trunk railways from different parts of the
States and Canada are focussed there, and cross the river by the
Cantilever and Suspension bridges below the Falls. The New York
Central and Hudson River, the Lehigh Valley, the Buffalo,
Rochester, and Pittsburgh, the Michigan Central, and the Grand
Trunk of Canada, are some of these lines. Draining as it does the
great lakes of the interior, which have a total area of 92,000
square miles, with an aggregate basin of 290,000 square miles, the
volume of water in the Niagara River passing over the cataract
every second is something like 300,000 cubic feet; and this, with
a fall of 276 feet from the head of the upper rapids to the
whirlpool rapids below, is equivalent to about nine million, or,
allowing for waste in the turbines, say, seven million horse-
power. Moreover, the great lakes discharging--into each other form
a chain of immense reservoirs, and the level of the river being
little affected by flood or drought, the supply of pure water is
practically constant all the year round. Mr. R. C. Reid has shown
that a rainfall of three inches in twenty-four hours over the
basin of Lake Superior would take ninety days to run off into Lake
Huron, which, with Lake Michigan, would take as long to overflow
into Lake Erie; and, therefore, six months would elapse before the
full effect of the flood was expended at the Falls.
The first outcome of the movement was the Niagara River Hydraulic
Power and Sewer Company, incorporated in 1886, and succeeded by
the Niagara Falls Power Company. The old plan of utilising the
water by means of an open canal was unsuited to the circumstances,
and the company adopted that of the late Mr. Thomas Evershed,
divisional engineer of the New York State Canals. Like the other,
it consists in tapping the river above the Falls, and using the
pressure of the water to drive the number of turbines, then
restoring the water to the river below the Falls; but instead of a
surface canal, the tail-race is a hydraulic tunnel or underground
conduit. To this end some fifteen hundred acres of spare land,
having a frontage just above the upper rapids, was quietly secured
at the low price of three hundred dollars an acre; and we believe
its rise in value owing to the progress of the works is such that
a yearly rental of two hundred dollars an acre can even now be got
for it. This land has been laid out as an industrial city, with a
residential quarter for the operatives, wharves along the river,
and sidings or short lines to connect with the trunk railways. In
carrying out their purpose the company has budded and branched
into other companies--one for the purchase of the land; another
for making the railways; and a third, the Cataract Construction
Company, which is charged with the carrying out of the engineering
works, for the utilisation of the water-power, and is therefore
the most important of all. A subsidiary company has also been
formed to transmit by electricity a portion of the available power
to the city of Buffalo, at the head of the Niagara River, on Lake
Erie, some twenty miles distant. All these affiliated bodies are,
however, under the directorate of the Cataract Construction
Company; and amongst those who have taken the most active part in
the work we may mention the president, Mr. E. D. Adams; Professor
Coleman Sellers, the consulting engineer; and Professor George
Forbes, F. R. S., the consulting electrical engineer, a son of the
late Principal Forbes of Edinburgh.
In securing the necessary right of way for the hydraulic tunnel or
in the acquisitom of land, the Company has shown consummate tact.
A few proprietors declined to accept its terms, and the Company
selected a parallel route. Having obtained the right of way for
the latter, it informed the refractory owners on the first line of
their success, and intimated that the Company could now dispense
with that. On this the sticklers professed their willingness to
accept the original terms, and the bargain was concluded, thus
leaving the Company in possession of the rights of way for two
tunnels, both of which they propose to utilise.
The liberal policy of the directors is deserving of the highest
commendation. They have risen above mere "chauvinism," and instead
of narrowly confining the work to American engineers, they have
availed themselves of the best scientific counsel which the entire
world could afford. The great question as to the best means of
distributing and applying the power at their command had to be
settled; and in 1890, after Mr. Adams and Dr. Sellers had made a
visit of inspection to Europe, an International Commission was
appointed to consider the various methods submitted to them, and
award prizes to the successful competitors. Lord Kelvin (then Sir
William Thomson) was the president, and Professor W. C. Unwin, the
well-known expert in hydraulic engineering, the secretary, while
other members were Professor Mascart of the Institute, a leading
French electrician; Colonel Turretini of Geneva, and Dr. Sellers.
A large number of schemes were sent in, and many distinguished
engineers gave evidence before the Commission. The relative merits
of compressed air and electricity as a means of distributing the
power were discussed, and on the whole the balance of opinion was
in favour of electricity. Prizes of two hundred and two hundred
and fifty pounds were awarded to a number of firms who had
submitted plans, but none of these were taken up by the Company.
The impulse turbines of Messrs. Faesch & Piccard, of Geneva, who
gained a prize of two hundred and fifty pounds, have, however,
been adopted since. It is another proof of the determination of
the Company to procure the best information on the subject,
regardless of cost, that Professor Forbes had carte blanche to go
to any part of the world and make a report on any system of
electrical distribution which he might think fit.
With the selection of electricity another question arose as to the
expediency of employing continuous or alternating currents. At
that time continuous currents were chiefly in vogue, and it speaks
well for the sagacity and prescience of Professor Forbes that he
boldly advocated the adoption of alternating currents, more
especially for the transmission of power to Buffalo. His proposals
encountered strong opposition, even in the highest quarters; but
since then, partly owing to the striking success of the Lauffen to
Frankfort experiment in transmitting power by alternating currents
over a bare wire on poles a distance of more than a hundred miles,
the directors and engineers have come round to his view of the
matter, and alternating currents have been employed, at all events
for the Buffalo line, and also for the chief supply of the
industrial city. Continuous currents, flowing always in the same
direction, like the current of a battery, can, it is true, be
stored in accumulators, but they cannot be converted to higher or
lower pressure in a transformer. Alternating currents, on the
other hand, which see-saw in direction many times a second, cannot
be stored in accumulators, but they can be sent at high pressure
along a very fine wire, and then converted to higher or lower
pressures where they are wanted, and even to continuous currents.
Each kind, therefore, has its peculiar advantages, and both will
be employed to some extent.
With regard to the engineering works, the hydraulic tunnel starts
from the bank of the river where it is navigable, at a point a
mile and a half above the Falls, and after keeping by the shore,
it cuts across the bend beneath the city of Niagara Falls, and
terminates below the Suspension Bridge under the Falls at the
level of the water. It is 6700 yards long, and of a horseshoe
section, 19 feet wide by 21 feet high. It has been cut 160 feet
below the surface through the limestone and shale, but is arched
with brick, having rubble above, and at the outfall is lined on
the invert or under side with iron. The gradient is 36 feet in the
mile, and the total fall is 205 feet, of which 140 feet are
available for use. The capacity of the tunnel is 100,000 horse-
power. In the lands of the company it is 400 feet from the margin
of the river, to which it is connected by a canal, which is over
1500 feet long, 500 feet wide at the mouth, and 12 feet deep.
Out of this canal, head-races fitted with sluices conduct the
water to a number of wheel-pits 160 feet deep, which have been dug
near the edge of the canal, and communicate below with the tunnel.
At the bottom of each wheel-pit a 5000 horse-power Girard double
turbine is mounted on a vertical shaft, which drives a propeller
shaft rising to the surface of the ground; a dynamo of 5000 horse-
power is fixed on the top of this shaft, and so driven by it. The
upward pressure of the water is ingeniously contrived to relieve
the foundation of the weight of the turbine shaft and dynamo.
Twenty of these turbines, which are made by the I. P. Morris
Company of Philadelphia, from the designs of Messrs. Faesch and
Piccard, will be required to utilize the full capacity of the
tunnel.
The company possesses a strip of land extending two miles along
the shore; and in excavating the tunnel a coffer-dam was made with
the extracted rock, to keep the river from flooding the works.
This dam now forms part of a system by which a tract of land has
been reclaimed from the river. Part of it has already been
acquired by the Niagara Paper Pulp Company, which is building
gigantic factories, and will employ the tailrace or tunnel of the
Cataract Construction Company. Wharfs for the use of ships and
canal boats will also be constructed on this frontage. By land and
water the raw materials of the West will be conveyed to the
industrial town which is now coming into existence; grain from the
prairies of Illinois and Dakota; timber from the forests of
Michigan and Wisconsin; coal and copper from the mines of Lake
Superior; and what not. It is expected that one industry having a
seat there will attract others. Thus, the pulp mills will bring
the makers of paper wheels and barrels; the smelting of iron will
draw foundries and engine works; the electrical refining of copper
will lead to the establishment of wire-works, cable factories,
dynamo shops, and so on. Aluminum, too, promises to create an
important industry in the future. In the meantime, the Cataract
Construction Company is about to start an electrical factory of
its own, which will give employment to a large number of men. It
has also undertaken the water supply of the adjacent city of
Niagara Falls. The Cataract Electric Company of Buffalo has
obtained the exclusive right to use the electricity transmitted to
that city, and the line will be run in a subway. This underground
line will be more expensive to make than an overhead line, but it
will not require to be renewed every eight to fifteen years, and
it will not be liable to interruption from the heavy gales that
sweep across the lakes, or the weight of frozen sleet: moreover,
it will be more easily inspected, and quite safe for the public.
We should also add that, in addition to the contemplated duplicate
tunnel of 100,000 horse-power, the Cataract Construction Company
owns a concession for utilising 250,000 horse-power from the
Horseshoe Falls on the Canadian side in the same manner. It has
thus a virtual monopoly of the available water-power of Niagara,
and the promoters have not the least doubt that the enterprise
will be a great financial success. Already the Pittsburg Reduction
Company have begun to use the electricity in reducing aluminum
from the mineral known as bauxite, an oxide of the metal, by means
of the electric furnace.
Another portion of the power is to be used to produce carbide of
calcium for the manufacture of acetylene gas. At a recent
electrical exhibition held in New York city a model of the Niagara
plant was operated by an electric current brought from Niagara,
450 miles distant; and a collection of telephones were so
connected that the spectator could hear the roar of the real
cataract.
Thanks to the foresight of New York State and Canada, the scenery
of the Falls has been preserved by the institution of public
parks, and the works in question will do nothing to spoil it,
especially as they will be free from smoke. Mr. Bogarts, State
Engineer of New York, estimates that the water drawn from the
river will only lower the mean depth of the Falls about two
inches, and will therefore make no appreciable difference in the
view. Altogether, the enterprise is something new in the history
of the world. It is not only the grandest application of
electrical power, but one of the most remarkable feats in an age
when romance has become science, and science has become romance.