I paid the electric and water bill this week.
His touch was like an electric shock, forcing her heart to pound.
I know it's him; he was riding around on his electric bike.
The electric company has probably been working all night.
Suddenly an electric shock seemed to run through Natasha's whole being.
In order to get rid of hydrogen, some oxygen is added to the helium, and the mixture exploded by an electric spark.
In order to get rid of hydrogen, some oxygen is added to the helium, and the mixture exploded by an electric spark.
The only sound in the apartment was the quiet whir of an electric clock.
The electric lamp a gives illumination of the webs in a dark field, nearly in the manner described for the Cape transit circle micrometer; the intensity of illumination is regulated by a carbon-resistance controlled by the screw b.
The coolness of his touch turned to gentle electric currents that worked their paths through her skull.
The coolness of his touch turned to gentle electric currents that worked their paths through her skull.
It looks so nice on that electric blue.
It looks so nice on that electric blue.
I could not in one hundred lifetimes make a working electric lamp, even knowing what I know now.
In dry weather the electric potential in the atmosphere is normally positive relative to the earth, and increases with the height.
There was no other purr aside from the constant, low hum similar to the hum surrounding electric wires.
His touch turned electric, and his magic skimmed her blood.
"What happened to your electric razor?" she asked as she watched him shave.
The iceman delivered ice for your icebox until the electric freezer put him out of business.
You must be ill to shiver like that, he added, noticing that Prince Andrew winced as at an electric shock.
The air between them was electric, her breathing uneven.
One hundred years ago the stream was damned by the Ouray Electric Power and Light Company.
By the time she reached the cliff Jule indicated the next day, Yully's soul was humming like an electric wire.
The small kitchen showed signs of its past life, before the addition of a modern sink and electric stove.
It has a motor... an electric motor and he's on a narrow trail!
Every morning she shaved him with an electric razor.
Kiki whirled from his position before the hearth, his oriental features set off by electric turquoise eyes.
Kiki whirled from his position before the hearth, his oriental features set off by electric turquoise eyes.
It is served by the Grand Trunk railway and by two electric lines to Detroit.
"Maybe I can trace his electric bike," Betsy said.
Hitherto the large bill for electric energy has debarred the general use of electrical heating, in spite of its numerous advantages.
The city owns its water-supply system and owns and operates its gas plant; an electric plant, privately owned, lights the streets and many houses.
It is served by the Missouri Pacific, the St Louis & San Francisco, the Missouri, Kansas & Texas, and the Kansas City Southern railways, and by interurban electric lines.
At its falls from Lake of the Woods is one of the greatest and most easily utilized water-powers in the world, and from falls lower down the river electric power for the city of Winnipeg is obtained.
I told him we were trying to trace the electric bike by its model but asked about checking hospitals.
I've got the name of a sex offender who bought a Volt Wheel electric bike in Oxnard, California.
He also made important contributions to the mathematical theory of electrodynamics, and in papers published in 1845 and 1847 established mathematically the laws of the induction of electric currents.
From it the exact time is conveyed each day at one o'clock by electric signal to the chief towns throughout the country; British and the majority of foreign geographers reckon longitude from its meridian.
And this is when he is carried out of himself, when the discordant qualities of his genius are, so to say, fused together by the electric spark of an immediate inspiration.
One was an electric bill, but the other was addressed to Sharon Dobson, Brownsville, Texas.
The city has extensive manufactures of heavy machinery, electric supplies, brass and copper products and silk goods.
It is served by the Morris & Essex division of the Delaware, Lackawanna & Western railway and by the Orange branch of the Erie (the former having three stations in the city - Grove Street, East Orange and Brick Church), and is connected with Newark, Orange and West Orange by electric line.
The city is generously provided with all the modern public services, including two street car lines, local and long distance telephone lines, electric power and light, and waterworks.
Of late years many experiments have been made on the influence of electric fields or currents on plant growth.
Of late years many experiments have been made on the influence of electric fields or currents on plant growth.
Vancouver has well-paved streets and is well supplied with water, electric lighting, electric cars and all the improvements of a modern city.
Electric power generated by steam is now commonly used in Buenos Aires and other large cities for driving light machinery.
It was not until the middle of the 18th century that experiments due to Benjamin Franklin showed that the electric phenomena of the atmosphere are not fundamentally different from those produced in the laboratory.
Let a conductor, say a metallic sphere, be supported by a metal rod of negligible electric capacity whose other end is earthed.
It is served by the New York, New Haven & Hartford railway, and by interurban electric lines running N., S.
Another opportunity will present itself I'm sure, but not where I might be identified with my perfect house on wheels and electric bicycle.
Whatever may be the shape or size of the particles, there is no scattered light in a direction parallel to the primary electric displacements.
Electric tramways serve the principal thoroughfares and suburbs.
The industries are equal in importance to the transit trade, and embrace metalworking, ironfounding and machine building, the manufacture of electric plant, celluloid, automobiles, furniture, cables and chemicals, sugar refining, cigar and tobacco making, and brewing.
An electric tramway has been constructed from Rome to Ostia and thence to the seashore, now some 2 m.
In 1882 Jenkin invented an automatic method of electric transport for goods - "telpherage" - but the completion of its details was prevented by his death on the 12th of June 1885.
It is served by the Atlantic Coast Line, the Seaboard Air line, the Southern, the New York, Philadelphia & Norfolk, the Chesapeake & Ohio, the Norfolk & Western, the Norfolk & Southern and the Virginian railways, by many steamship lines, by ferry to Portsmouth (immediately opposite), Newport News, Old Point Comfort and Hampton, and by electric lines to several neighbouring towns.
Yeah, he was on a bike but it wasn't electric.
The following branches have especially felt his influence: - chemical physics, capillarity and viscosity, theory of gases, flow of liquids, photography, optics, colour vision, wave theory, electric and magnetic problems, electrical measurements, elasticity, sound and hydrodynamics.
The line crossing Australia which was thus explored has since been occupied by the electric telegraph connecting Adelaide, Melbourne, Sydney, and other Australian cities with London.
It is served by the Maine Central railway, by several electric lines, and by steamboat lines to Portland, Boston and several other ports.
During the three years he held this position he carried out researches on the contact of elastic solids, hardness, evaporation and the electric discharge in gases, the last earning him the special commendation of Helmholtz.
Jones, and published in three volumes: Electric Waves (1893), Miscellaneous Papers (1896), and Principles of Mechanics (1899).
Belleville is served by the Illinois Central, the Louisville & Nashville, and the Southern railways, also by extensive interurban electric systems; and a belt line to O'Fallon, Illinois, connects Belleville with the Baltimore & Ohio South Western railway.
It is served by the New York, New Haven & Hartford railway, and is primarily a residential suburb of Boston, with which it is connected by electric lines.
Manchester is served by the New York, New Haven & Hartford railway and by electric line connecting with Hartford, Rockville and Stafford Springs.
It is served by the Delaware, Lackawanna & Western railway, and by the Oneonta & Mohawk Valley electric line connecting with the New York Central railway at Herkimer.
The different kinds of motive power used to actuate cranes - manual, steam, hydraulic, electric - give a further classification.
The electric transmission of energy can be performed with an efficiency not reached by any other method, and the electric motor readily adapts itself to cranes.
For dock-side jib cranes the use of electric power is making rapid strides.
Cranes driven by shafting, or by mechanical power, have been largely superseded by electric cranes, principally on account of the much greater economy of transmission.
For many years the best workshop travellers were those driven by quick running ropes; these performed admirable service, but they have given place to the more modern electric traveller.
In electric cranes a useful method is to arrange the connexions so that the lifting motor acts as a dynamo, and, driven by the energy of the falling load, generates a current which is converted into heat by being passed through resistances.
In the second, or " braking off " method, the brake is automatically applied by a spring or weight, and is released either mechanically or, in the case of electric cranes, by the pull of a solenoid or magnet which is energized by the current passing through the motor.
This method of working is very suitable for electric dock-side cranes of capacities up to about 5 or 7 tons, and for overhead travellers where the height of lift is moderate.
In electric cranes the motor is connected to the barrel, either in a similar manner by spur gear or by worm gear.
Electric motors for barrel cranes are not essentially different from those used for other purposes, but in proportioning the sizes the intermittent output has to be taken into consideration.
In practice, the load factor for electric crane motors varies from 3 to s.
when actually lifting at full speed the mechanical work of lifting represents about 72%° of the electric energy put into the lifting motor.
The motor in most common use for electric cranes is the series wound, continuous current motor, which has many advantages.
Tests of the comparative efficiencies of hydraulic and electric cranes tend to show that, although they do not vary to any very considerable extent with full load, yet the efficiency of the hydraulic crane falls away very much more rapidly than that of the electric crane when working on smaller loads.
This drawback can be corrected to a slight extent by furnishing the hydraulic crane with more than one cylinder, and thus compounding it, but the arrangement does not give the same economical range of load "as in an electric crane.
In first cost the hydraulic crane has the advantage, but the power mains are much less expensive and more convenient to arrange in the electric crane.
Where electric or hydraulic cranes are worked from a central station the speed is greater, and may be roughly represented by V =5 +30o/T; e.g.
The lifting speed of electric travellers is generally less, because the lift is generally much shorter, and may in ordinary cases be taken as V=3+85/T.
In addition to the brakes on the lifting gear of cranes it is found necessary, especially in quickrunning electric cranes, to provide a brake on the subsidiary motions, and also devices to stop the motor at the end of the lift or travel, so as to prevent over-running.
13 shows an electric crane of this class.
16 a somewhat similar machine worked by electric power.
Nearly all recent advances in crane design are the result of the introduction of the electric motor.
- Although the history of practical electric telegraphy does not date much further back than the middle of the, 9th century, the idea of using electricity for telegraphic purposes is much older.
This, with proper apparatus for originating electric currents at one end and for discovering the effects produced by them at the other end, constitutes an electric telegraph.
Faraday's term " electrode," literally " a way (650s) for electricity to travel along," might be well applied to designate the insulated conductor along which the electric messenger is despatched.
The apparatus for generating the electric action at one end is commonly called the transmitting apparatus or instrument, or the sending apparatus or instrument, or sometimes simply the transmitter or sender.
The finished core changes rapidly in its electric qualities at first, and is generally kept for a stated interval of time before being subjected to the specified tests.
The subjection of the core to a hydraulic pressure of four tons to the square inch and an electric pressure of 5000 volts from an alternating-current transformer has been adopted, by one manufacturer at least, to secure the detection of masked faults which might develop themselves after submergence.
In this apparatus electric A B C currents are generated by turning a handle (placed in front of the instrument), which is geared, in the instru ment.
This system of telegraphic printing has a great advantage over the step-by-step system in avoiding the necessity for the rapidly acting electric escapement, which, however skilfully planned and executed, is always liable to failure when worked too rapidly.
In the Korn apparatus the light from a Nernst electric lamp is concentrated to a point by means of a lens on the original picture, which is wound on a glass cylinder in the shape of a transparent photographic film.
The transmitted signals or electric impulses, which on a land line are sharply defined when received, become attenuated and prolonged in the case of a long cable, and are unable to actuate the.
The general principle on which the instruments for working long submarine cables are based is that of making the moving parts very light and perfectly free to follow the comparatively slow rise and fall of the electric impulses or waves.
indicator, suitably supported, a to-and-fro motion was recorder given by the electromagnetic actions due to the electric currents constituting the signals.
When therefore the signalcoil moves in obedience to the electric signal-currents passed through it, the motion communicated to the siphon is recorded on the moving slip of paper by a wavy line of ink-marks very close together.
The Electric Telegraph Company, formed to undertake the business of transmitting telegrams, was incorporated in 1846.
During this period the Electric Telegraph Company's average receipts per message fell from 4s.
Scudamore, second secretary to the Post Office, to inquire and report whether the electric telegraph service could be beneficially worked by the Post Office, and whether it would entail any very large expenditure on the.
The stock of the Electric and International Company, the return on which had reached 10 per cent.
In 1868 the length of electric telegraph lines belonging to the companies was 16,643 m., and of those belonging to the railway companies 4872 m., or a total of 21,515.
Visiting England in 1856, Field entered into an agreement with Bright and with John Watkins Brett, who with his brother Jacob had proposed the constructing of an Atlantic cable eleven years previously, with the object of forming a company for establishing and working electric telegraphic communication between Newfoundland and Ireland.
Closely analogous to the action of the state in the cases referred to is the action taken by municipal authorities with the authority of the legislature in competing with or superseding private companies for the supply of electric light, gas, water, tramways and other public services..
Reports to the Postmaster-General upon proposals for transferring to the Post Of f ice the Telegraphs throughout the United Kingdom (1868); Special Reports from Select Committee on the Electric Telegraphs Bills (1868, 1869); Report by Mr Scudamore on the reorganization of the Telegraph system of the United Kingdom (1871); Journ.
- Wireless Telegraphy The early attempts to achieve electric telegraphy involved the use of a complete metallic circuit, but K.
Morse showed, by experiments made in 1842 on a canal at Washington, that it was possible to interrupt the metallic electric circuit in two places and yet retain power of electric Morse.
Under these circumstances a small portion of the current from the battery is shunted through the galvanometer circuit, and can be used to make electric signals.
He found, as others have dune, that if a battery, dynamo or induction coil has its terminals connected to the earth at two distant places, a system of electric currents flows between these points through the crust of the earth.
In this manner Trowbridge showed that signalling might be carried on over considerable distances by electric conduction through the earth or water between places not metallically connected.
All these older methods have, however, been thrown into the background and rendered antiquated by inventions which have grown out of Hertz's scientific investigations on the production of electric waves.
p. 203) noticed that a single electric spark about an inch long thrown on to a circuit of wire in an upper room could magnetize steel needles included in a parallel circuit of wire placed in a cellar 30 ft.
Some curious distance-phenomena connected with electric sparks were observed in 1875 by Edison (who referred them to a supposed new " aetheric force "), and confirmed by Beard, S.
He discovered a fact subsequently rediscovered by others, that a tube of metallic filings, loosely packed, was sensitive to electric sparks made in its vicinity, its electrical resistance being reduced, and he was able to detect effects on such a tube connected to a battery and telephone at a distance of 500 yds.'
of a condenser produces an electric spark which under proper conditions creates an effect propagated out into space as an electric wave.
The peculiar action of electric sparks and waves in reducing the resistance of discontinuous conductors was rediscovered and investigated by Calzecchi Onesti,' by Branly, 2 Dawson Turner, 3 Minchin, Lodge, 4 and many others.
Lodge particularly studied the action of electric waves in reducing the resistance of the contact between two metallic surfaces such as a plate and a point, or two balls, and named the device a coherer."
On creating an electric spark or wave in the neighbourhood of the tube the resistance suddenly falls to a few ohms and the cell sends a current through it.
But, as Branly showed, it is not universally true that the action of an electric wave is to reduce the resistance of a tube of powdered metal or cause the particles to cohere.
Marconi gave great attention to the improvement of devices for the detection of electric waves..
This form of electric wave detector proved itself to be far more certain in operation and sensitive than anything previously invented.
The object which Marconi had in view was not merely the detection of electric waves, but their utilization in practical wireless telegraphy.
Marconi, however, made the important discovery that if his sensitive tube or coherer had one terminal attached to a metal plate lying on the earth, or buried in it, and the other to an insulated plate elevated at a height above the ground, it could detect the presence of very feeble electric waves of a certain kind originating at a great distance.
When the discharge takes place the ends of the lines of electric force abutting on the wire run down it and are detached in the form of semiloops of electric force which move outwards with their ends on the surface of the earth.
The magnetic and electric forces are directed alternately in one direction and the other, and at distances which are called multiples of a wave length the force is in the same direction at the same time, but in the case of damped waves h.as not quite the same intensity.
Fleming's Electric Wave Telegraphy, by permission of Longmans, Green & Co.
' For a more complete account of the nature of an electric wave the reader is referred to Hertz's Electric Waves, and to the article Electric Wave.
See also The Principles of Electric Wave Telegraphy, by J.
- Marconi Sensitive Metallic Filings Tube or Electric Wave Detector.
This periodic distribution in time and space constitutes an electric wave proceeding outwards in all directions from the sending antenna.
These trains are produced by pressing the key in the primary circuit of the induction coil for a longer or shorter time' and generating a long or short series of oscillatory electric sparks between the spark balls with a corresponding creation of trains of electric waves.
He thus produced in 1896 for the first time an operative apparatus of electric wave telegraphy.
Marconi's successes and the demonstrations he had given of the thoroughly practical character of this system of electric wave telegraphy stimulated other inventors to enter the same field of labour, whilst theorists began to study carefully the nature of the physical operations involved.
It was also recognized that what is required at the transmitting end is the establishment of powerful electric oscillations in the sending antenna, which create and radiate their energy in the form of electric waves having their magnetic force component parallel to the earth's surface and their electric component perpendicular to it.
We now consider the more recent appliances for electric wave telegraphy under the two divisions of transmitting and receiving apparatus.
This creates rapid variations in electric and magnetic force round the antenna and detaches energy from it in the form of an electric wave.
The antenna has at one moment a static electrical charge distributed upon it, and lines of electric force stretch from it to the surrounding earth.
At the next instant it is the seat of an electric current and is surrounded by closed lines of magnetic force.
These static and kinetic conditions succeed each other rapidly, and the result is to detach or throw off from the antenna semi-loops of electric force, which move outwards in all directions and are accompanied by expanding circular lines of magnetic force.
In many cases additional condensers or inductance coils are inserted in various places so that the arrangement is somewhat disguised, but by far the larger part of the electric wave wireless telegraphy in 1907 was effected by transmitters having antennae either inductively or directly coupled to a closed condenser circuit containing a spark gap.
In one of these ways the oscillations can be created or stopped at pleasure in the radiating antenna, and hence groups of electric waves thrown off at will.
In order to produce electric oscillations in the system, the first or alternating current transformer must charge the condenser connected to its secondary terminals, but must not produce a permanent electric arc between the balls.
In the case of transmitters constructed as above described, in which the effective agent in producing the electric waves radiated is the sudden discharge of a condenser, it should be noticed that what is really sent out is a train of damped or decadent electric waves.
When electric oscillations are set up in an open or closed electric circuit having capacity and inductance, and left to themselves, they die away in amplitude, either because they dissipate their energy as heat in overcoming the resistance of the circuit, or because they radiate it by imparting wave motion to the surrounding ether.
Such a sequence of decreasing electric oscillations and corresponding set of waves is called a damped train.
Allusion is made below to recent work on the production of undamped trains of electric waves.
The electric waves coming through space from the sending station strike against the receiving antenna and set up in it high frequency alternating electromotive forces.
Popoff employed an electromagnetic tapper, in fact the mechanism of an electric bell with the gong removed, for this purpose.
It was then found that when electric waves fell on the antenna a sound was heard in the telephone as each wave train passed over it, so that if the wave trains endured for a longer or shorter time the sound in the telephone was of corresponding duration.
perfect electrical contact between the steel and mercury for low voltage currents, but when electric oscillations were passed through the junction it was pierced and good electrical contact established as long as the oscillations continued.
This device was converted into an electric wave detector as follows :-The mercury-steel junction was acted upon by the electromotive force of a shunted single cell and a siphon recorder was inserted in series.
When electric waves fell on the antenna they caused the mercury-steel junction to become conductive during the time they endured, and the siphon recorder therefore to write signals consisting of short or long deflexions of its pen and therefore notches of various length on the ink line drawn on the strip of telegraphic tape.
Fleming, The Principles of Electric Wave Telegraphy and Telephony, p. 416, 2nd ed.
The next class of wave or oscillation detector is the magnetic detector depending upon the power of electric oscillations to affect the magnetic state of iron.
Rutherford examined it very carefully, and produced a magnetic detector for electric waves depending upon the power of electric oscillations in a coil to demagnetize a saturated bundle of steel wires placed in it.
Rutherford used this detector to make evident the passage of an electric or Hertzian wave for half a mile across Cambridge, England.
Wilson constructed various forms of electric wave detector depending on this same principle.
In 1902 Marconi invented two forms of magnetic detector, one of which he developed into an electric wave detector of extraordinary delicacy and utility.
A third class of electric wave detector depends upon the power of electric oscillations to annul the electrolytic polarization of electrodes of small surface immersed in an electrolyte.
If, however, one electrode of this cell is connected to the earth and the other to a receiving antenna and electric waves allowed to fall on the antenna, the oscillations passing through the electrolytic cell will remove the polarization and L temporarily decrease the resistance of the cell.
A fourth class of electric wave detector comprises the thermal detectors which operate in virtue of the fact that electric oscillations create heat in a fine wire through which they pass.
If a loop of very fine platinum wire, prepared by the Wollaston process, is included in an exhausted glass bulb like an incandescent lamp, then when electric oscillations are sent through it its resistance is increased.
47) and when electric waves fall on A they excite oscillations in the fine wire resistance R and increase the resistance, and so upset the balance of the bridge and cause the galvanometer to deflect.
Such a bolometer receiver has been used by C. Tissot (Comptes rendus, 1904, 137, p. 846) and others as a receiver in electric wave telegraphy.
Fessenden employed a simple fine loop of Wollaston platinum wire in series with a telephone and shunted voltaic cell, so that when electric oscillations passed through the fine wire its resistance was increased and the current through the telephone suddenly diminished (R.
Fleming discovered that if the filament is made incandescent by the current from an insulated battery there is a unilateral conductivity of the rarefied gas between the hot filament and the metal plate, such that if the negative terminal of the filament is connected outside the lamp through a coil in which electric oscillations are created with the platinum plate, only one half of the oscillations are permitted to pass, viz., those which carry negative electricity from the hot filament to the cooled plate through the vacuous space.
Pierce, The Physical Review, July 1907, March 1909, on crystal rectifiers for electric oscillations.
The good electric radiators may be compared with good thermal radiators, such as a vessel coated with lamp black on the outside, and the bad electric radiators to poor thermal radiators, such as a silver vessel highly polished on its exterior.
When electric oscillations are set up in these two classes of electric radiators, the first class send out a highly damped wave train and the second a feeble damped wave train provided that they have sufficient capacity or energy storage and low resistance.
an antenna of suitable capacity and inductance to a nearly closed electric circuit consisting of a condenser of large capacity, a spark gap and an inductance of low resistance.
When oscillations are excited in this last circuit they communicate them to the antenna provided this last circuit is tuned or syntonized to the closed circuit, and the radiating antenna has thus a large store of energy to draw upon and can therefore radiate prolonged trains of electric waves.
- Telluriumbismuth Vacuum Thermal Detector for Electric Oscillations.
These mechanical qualities correspond to inductance and capacity in electric circuits.
This receiver therefore, like the transmitter, consists of an open and a closed electric oscillation circuit inductively connected together; also the two circuits of the receiver must be syntonized or tuned both to each other and to those of the transmitter.'
When this is done we have a syntonic system which is not easily affected by electric waves of other than the right period or approximating thereto.
Slaby in Berlin shortly afterwards made a similar exhibition of syntonic electric wave telegraphy' O.
Lodge had previously described in 1897 a syntonic system of electric wave telegraphy, but it had not been publicly seen in operation prior to the exhibitions of Marconi and Slaby.'
At this stage it may be convenient to outline the progress of electric wave telegraphy since 1899.
Marconi's success in bridging the English Channel at Easter in 1899 with electric waves and establishing practical wireless telegraphy between ships and the shore by this means drew public attention to the value of the new means of communication.
Braun showed that oscillations suitable for the purposes of electric wave creation in wireless telegraphy could be set up in a circuit consisting of a Leyden jar or jars, a spark gap and an inductive circuit, and communicated to an antenna either by inductive or direct coupling (Brit.
All of them couple the transmitting antenna directly or inductively to a capacity-inductive circuit serving as a storage of energy, and all of them create thereby electric waves of the same type moving over the earth's surface with the magnetic force of the wave parallel to it.
From and after that time the British Admiralty and the navies of other countries began to give great attention to the development of electric wave telegraphy.
In January 1901 he telegraphed without difficulty by electric waves from the Isle of Wight to the Lizard, viz.
200 m., and he considered that the time had come for a serious attempt to be made to communicate across the Atlantic. A site for a first Transatlantic electric wave power station was secured at Poldhu, near Mullion in south Cornwall, by the Marconi Company, and plans arranged for an installation.
The special electrical engineering arrangements employed at the outset for this first electric wave power station required to create the oscillations of the desired power were designed for Marconi by J.
long upheld by a box kite, and, employing a sensitive coherer and telephone as a receiver, he was able, on December 12, 1901, to hear " S " signals on the Morse code, consisting of three dots, which he had arranged should be sent out from Poldhu at stated hours, according to a preconcerted programme, so as to leave no doubt they were electric wave signals sent across the Atlantic and not accidental atmospheric electric disturbances.
This result created a great sensation, and proved that Transatlantic electric wave telegraphy was quite feasible and not inhibited by distance, or by the earth's curvature even over an arc of a great circle 3000 m.
In 1904 a regular system of communication of press news and private messages from the Poldhu and Cape Breton stations to Atlantic liners in mid-Atlantic was inaugurated, and daily newspapers were thenceforth printed on board these vessels, news being supplied to them daily by electric wave telegraphy.
A problem of great importance in connexion with electric wave telegraphy is that of limiting the radiation to certain directions.
Hertz had shown that the electric radiation from an oscillator See J.
Fleming, The Principles of Electric Wave Telegraphy (London, 1906), chap. vii.; also Cantor Lectures on Hertzian wave telegraphy, Lecture iv., Journ.
He operated with electric waves two or three feet in wave-length.
12039 of 1896) brought forward the idea of focusing a beam of electric radiation for telegraphic purposes on a distant station by means of parabolic mirrors, and tried this method successfully on Salisbury Plain up to a distance of about a couple of miles.
The process of reflection in the case of a wave motion involves the condition that the wave-length shall be small compared with the dimensions of the mirror, and hence the attempt to reflect and converge electric waves loon ft.
He showed that if an antenna were constructed with a short part of its length vertical and the greater part horizontal, the lower end of the vertical part being earthed, and if oscillations were created in it, electric waves were sent out most powerfully in the plane of the antenna and in the direction opposite to that in which the free end pointed.
It appears, however, to depend upon the fact that an electric arc is not like a solid conductor.
Increase in the voltage acting upon a solid conductor increases the current through it, but in the case of the electric arc an increase in current is accompanied by a fall in the difference of potential of the carbons, within certain limits, and the arc has therefore been said to possess a negative resistance.'
The electric arc is formed between cooled copper (positive) and carbon (negative) electrodes in an atmosphere of hydrogen or coal-gas.
Fleming, The Principles of Electric Wave Telegraphy, 1906, p. 73.
The scientific study of electric wave telegraphy has necessitated the introduction of many new processes and methods of electrical measurement.
The velocity of propagation of electric waves is the same as that of light, viz., about moo million feet, or 300 million metres, per second.
An immense mass of information has been gathered on the scientific processes which are involved in electric wave telegraphy.
Starting from an observation of Marconi's, a number of interesting facts have been accumulated on the absorbing effect of sunlight on the propagation of long Hertzian waves through space, and on the disturbing effects of atmospheric electricity as well as upon the influence of earth curvature and obstacles of various kinds interposed in the line between the sending and transmitting stations.4 Electric wave telegraphy has revolutionized our means of communication from place to place on the surface of the earth, making it possible to communicate instantly and certainly between places separated by several thousand miles, whilst The Electrician, 1904, 5 2, p. 407, or German Pat.
Fleming, " Electric Oscillations and Electric Waves," Cantor Lectures, Journ.
Soc. Arts, 1901, 49, p. 505; id., " Progress of Electric Space Telegraphy," Proc. Roy.
Fleming, Hertzian Wave Telegraphy (1905); id., The Principles of Electric Wave Telegraphy and Telephony (2nd ed., 1910); J.
Hertz, Electric Waves (1893); O.
Macdonald, Electric Waves (Cambridge, 1901); H.
The municipality owns and operates the waterworks and the electric lighting plant.
It is largely used for the purpose of making standard electric cells, such for example as the Weston cell.
On the 26th of August 1854 there appeared in L'Illustration (Paris) an interesting article by Charles Bourseul on the electric transmission of speech.
5 The writer recommended the use of a flexible plate at the source of sound, which would vibrate in response to the varying pressure of the bons' air, and thus open and close an electric circuit, and of a similar plate at the receiving station, which would be acted on electromagnetically and thus give out as many pulsations as there are breaks in the current.
The instrument was described in over fifty publications 6 in various countries, and was well known to physicists previous to Bell's introduction of the electric telephone as a competitor with the electric telegraph.
Reis caused a membrane to open and close an electric 2 See his Scientific Papers, P. 47.
These electric pulses were made to act on an electromagnet at the receiving station, which, in accordance with Page's discovery, gave out a sound of a pitch corresponding to the number of times it was magnetized or demagnetized per second.
His aim was the production, by means of the undulations of pressure on a membrane caused by sound, of an electric current the strength of which should at every instant vary directly as the pressure varied).
The receiver was based on the change of friction produced by the passage of an electric current through the point of contact of certain substances in relative motion.
The varying pressure on A, when a sound was produced near it, caused corresponding variations in the pressure on the carbon powder, and this produced similar variations in its electric resistance.
In these experiments the electric current passed through the fingers of the operator's hand, which thus took the place of the spring in Edison's apparatus.
Varley, who proposed to make use of it in a telegraphic receiving instrument.4 In Dolbear's instrument one plate of a condenser was a flexible diaphragm, connected with the telephone line in such a way that the varying electric potential produced by the action of the transmitting telephone caused an increased or diminished charge in the condenser.
Hughes, while engaged in experiments upon a Bell telephone in an electric circuit, discovered that a peculiar noise was produced whenever two hard electrodes, such as two wires, were - drawn across each other, or were made to touch each other with a variable degree of firmness.
The single-wire earthed circuits used in the early days of telephony were subject to serious disturbances from the induction caused by currents in neighbouring telegraph and electric light wires, and from the varying potential of the earth due to natural or artificial causes.
The introduction of electric tramways caused an enormous increase in disturbances of this class.
II and 12 indicate typical subscriber's and connecting-cord circuits as equipped by the Western Electric Company.
- Typical Cord Circuit, Western Electric Co.'s System, No.
Reports of Select Committee on Telephone and Telegraph Wires (1885), of Select Committee on Telegraph Bill (1892), of Joint Committee of the House of Lords and the House of Commons on Electric Powers (Protective Clauses) (1893), of Select Committee on Telephone Service (1895), of Select Committee on Telephones (1898), and of Select Committee on Post Office (Telephone) Agreement (1905); Treasury Minutes (1892 and 1899); Annual Reports of the Postmaster-General; Report to the Treasury by Sheriff Andrew Jameson on Glasgow Telephone Enquiry (1897); H.
If the available water-power of Italy, already very considerable, be harnessed, converted into electric power (which is already being done in some districts), and further increased by reafforestation, the effect upon the industries of Italy will be incalculable, and the importation of coal will be very materially diminished.
The electric power required fcir the tramways and the illuminatiQn of Rome is entirely supplied by turbines situated at Tivoli, and this is the case elsewhere, and the harnessing of this waterpower is capable of very considerable extension.
Great progress has been made in the manufacture of machinery; locomotives, railway carriages, electric tram-cars, &c., and machinery of all kinds, are now largely made in Italy itself, especially in the north and in the neighborhood of Naples.
of electric tramways.
In the south they are rare, on account partly of the mountainous character of the country, and partly of the scarcity of traffic. All the important towns of Italy are provided with internal electric tramways, mostly with overhead wires.
Another convenient arrangement is the provision of letter-boxes on electric tramcars in some cities.
It is served by the Illinois Central and the Chicago & Alton railways and by the Illinois Traction Interurban Electric line.
The principal thoroughfares are served by electric tramway.
Westboro is served by the Boston & Albany railway and by interurban electric lines.
It is served by the Chicago & North-Western railway, by interurban electric lines connecting with Chicago and Milwaukee, and by freight and passenger steamship lines on Lake Michigan.
Louis, the Pittsburg, Cincinnati, Chicago & St Louis (Pennsylvania system), the Baltimore & Ohio, the Ohio Central, the Norfolk & Western, the Hocking Valley, and the Cleveland, Akron & Columbus (Pennsylvania system) railways, and by nine interurban electric lines.
There are large metallurgical works with electric motive power close to the town.
Hanoi resembles a European city in the possession of wide well-paved streets and promenades, systems of electric light and drainage and a good water-supply.
(electric), and by steamboat lines to Cincinnati, Louisville and other river ports.
To enable the indications of the log register on the taffrail to be recorded in the chart room or any other part of the vessel as desired, a chart room electric register has been introduced.
By means of an electric installation between the log register aft and the electric register in the chart room, every tenth of a mile indicated by the former is recorded by the latter.
long, connecting the several railways and carrying more than 1,000,000 freight cars annually; and an extensive electric street railway system, with more than 150 m.
The city is lighted by gas and electricity, - it was one of the first cities in the United States to adopt electric lighting, - and has a good watersupply system, owned by a private corporation, with a 41 acre filter plant of 18,000,000 gallons per diem capacity and an additional supply of water pumped from deep wells outside the city.
Frankfort is served by the Chicago, Indianapolis & Louisville, the Lake Erie & Western, the Vandalia, and the Toledo, St Louis & Western railways, and by the Indianapolis & North -Western Traction Interurban railway (electric).
The streets are lighted with electricity; and there are electric street railways and telephones in the city.
The city is well drained and possesses a good water supply; it is lighted by electricity and has an electric car system.
In both states, the Commissions have power over electric railways and local public utilities furnishing heat, light and power, as well as over steam railway transportation, and the Wisconsin Commission also has control over telephone companies.
the item " passengers killed " includes those on some electric railways, which presumably are not covered in the statement here given; also passengers in freight trains, &c. Under `' employees " this table includes men in shops, &c., not shown in Table XIV.
The weight required to cause the downward motion is obtained either by means of the material which has to be transported to the bottom of the hill or by water ballast, while to aid and regulate the motion generally steam or electric motors are arranged to act on the main drums, round which the cable is passed with a sufficient number of turns to prevent slipping.
One of the advantages of electric trains on the multiple control system is that they economize terminal accommodation, because they can be driven from either end indifferently, and therefore avoid the necessity for tracks by which engines can change from one end of the train to the other.
For the illumination of large stations by night electric arc lamps are frequently employed, but some authorities favour high-pressure incandescent gas-lighting.
Every axle of an electric locomotive may thus be subjected to a torque, and the large weight which must be put on one pair of wheels in order to secure sufficient adhesion when all the driving is done from one axle may be distributed through as many pairs of wheels as desired.
This perfection of distribution is practically attained in present-day practice by the multiple control system of operating an electric train, where motors are applied to a selected number of axles in the train, all of them being under the perfect control of the driver.
For suburban traffic with a service at a few minutes' interval and short distances between the stations electric traction has proved itself to be superior in many respects to the steam locomotive, but for main line traffic and long distance runs it has not yet been demonstrated that it is commercially feasible, though it is known to be practically possible.
For the methods of electric traction see Traction; the remainder of the present article will be devoted to the steam locomotive.
When the service is frequent enough to give a good power factor continuously, the steam locomotive cannot compete with the electric motor for the purpose of quick acceleration, because the motors applied to the axles of a train may for a short time absorb power from the central station to an extent far in excess of anything which a locomotive boiler can supply.
Cars of this saloon type have been introduced into England for use on railways which have adopted electric traction, but owing to the narrower loading gauge of British railways it is not usually possible to seat four persons across the width of the car for its whole length, and at the ends the seats have to be placed along the sides of the vehicle.
Cars built almost entirely of steel, in which the proportion of wood is reduced to a minimum, are used on some electric railways, in order to diminish danger from fire, and the same mode of construction is also being adopted for the rolling stock of steam railways.
On electric railways the trains are heated by electric heaters.
Electric light is free from this drawback.
Its promoters recognized the unsuitability of ordinary steam locomotives for underground railways, and intended to work it by means of a moving cable; but before it was completed, electric traction had developed so far as to be available for use on such lines.
- Section of Tunnel and Electric Locomotive, City & South London railway.
- Electric Underground Railway, Budapest.
This system has the advantage of the greatest convenience in operation, no lifts being required, since the distance from the street surface to the station platform is about 12 to 15 ft.; it has the disadvantages, however, of necessitating the tearing up of the street surface during construction, and the readjustment of sewer, water, gas and electric mains and other subsurface structures, and of having the gradients partially dependent on the surface topography.
The cost of intra-urban railways depends not only on the type of construction, but more especially upon local conditions, such as the nature of the soil, the presence of subsurface structures, like sewers, water and gas mains, electric conduits, &c.; the necessity of permanent underpinning or temporary supporting of house foundations, the cost of acquiring land passed under or over when street lines are not followed, and, in the case of elevated railways, the cost of acquiring easements of light, air and access, which the courts have held are vested in the abutting property.
- New York Rapid Transit railway, showing also the tracks and conduits of the electric surface tramway.
It is served by the Erie, the Delaware, Lackawanna & Western, and the Lackawanna & Wyoming Valley (electric) railways.
outside the walls, but this distance has since been covered by an electric tramway.
It is served by the Southern Pacific and the Santa Fe railway systems, both transcontinental; and is connected by electric lines (and ferry) with San Francisco, and by five electric lines with Oakland.
It is served by the New York, New Haven & Hartford railway, by inter-urban electric lines and in summer by steamers to Boston.
Parkersburg is served by the Baltimore & Ohio, the Baltimore & Ohio Southwestern, and the Little Kanawha railways, by electric railway to Marietta, Ohio, and by passenger and freight boats to Pittsburg, Cincinnati, intermediate ports, and ports on the Little Kanawha.
He treated the resultant electric force at any point as analogous to the flux of heat from sources distributed in the same manner as the supposed electric particles.
But this was based upon the assumption of a distance-action between electric particles, the intensity of which depended on their relative motion as well as on their position.
It is served by the Lehigh Valley and the Philadelphia & Reading railways, and by the electric lines of the Schuylkill Railway Company and the Shamokin & Mount Carmel Transit Company.
Pop. (1900) 10,588, of whom 1804 were foreign-born; (1 9 10 census) 9535 It is served by the Chicago, Burlington & Quincy, and the Chicago, Rock Island & Pacific railways, by interurban electric railways, and by the Illinois & Michigan Canal.
The city is served by the Cleveland, Cincinnati, Chicago & St Louis, and the Pittsburg, Cincinnati, Chicago & St Louis railways, and is connected with Indianapolis and with Louisville, Ky., by an electric interurban line.
There he made the acquaintance of Thomas Andrews, whom he joined in researches on the density of ozone and the action of the electric discharge on oxygen and other gases, and by whom he was introduced to Sir W.
It is served directly by the Chesapeake & Ohio railway, and indirectly by the New York, Philadelphia & Norfolk (Pennsylvania System), passengers and freight being carried by steamer from the terminus at Cape Charles; by steamboat lines connecting with the principal cities along the Atlantic coast, and with cities along the James river; by ferry, connecting with Norfolk and Portsmouth; and by electric railway (3 m.) to Hampton and (1 2 m.) to Newport News.
Portsmouth is served by the Boston & Maine railway, by electric lines to neighbouring towns, and in summer by a steamboat daily to the Isles of Shoals.
Special progress has been made in the production of mirrors, electric lamps, candelabra and mosaics.
As the building of steam railways lessened, the building of suburban and interurban electric railways was begun, and systems of these railways have been rapidly extended until all the more populous districts are connected by them.
around the peninsula are spanned by causeways and bridges, East Boston only, that the harbours may be open to the navyyard at Charlestown, being reached by ferry (1870), and by the electric subway under the harbour.
One of the great public works of Boston is its subway for electric trams, about 3 m.
Heating spirits of hartshorn, he was able to collect "alkaline air" (gaseous ammonia), again because he was using mercury in his pneumatic trough; then, trying what would happen if he passed electric sparks through the gas, he decomposed it into nitrogen and hydrogen, and "having a notion" that mixed with hydrochloric acid gas it would produce a "neutral air," perhaps much the same as common air, he synthesized sal ammoniac. Dephlogisticated air (oxygen) he prepared in August 1774 by heating red oxide of mercury with a burning-glass, and he found that in it a candle burnt with a remarkably vigorous flame and mice lived well.
An electric tramway connects Margate with Broadstairs and Ramsgate, and during the season it is served by numerous pleasure steamers from London.
New Haven is served by the main line and five branches of the New York, New Haven & Hartford railway, by three inter-urban electric lines and by two steamship lines connecting with New York.
It is served by the New York, New Haven & Hartford and the Boston & Albany (New York Central & Hudson River) railways, and by two inter-urban electric lines.
It is served by the Chesapeake & Ohio (being a terminal of the Lexington and Big Sandy Divisions) and the Norfolk & Western railways, and is connected with Huntington, West Virginia, by an electric line.
Sterling is served by the Chicago & Northwestern and the Chicago, Burlington & Quincy railways, and by inter-urban electric railway to Dixon, 12 m.
In Saybolt's Electric Tester (1879) ignition is effected by a spark from an induction-coil passing between platinum points placed at a fixed distance above the oil.
AMPEREMETER, or Ammeter, an instrument for the measurement of electric currents in terms of the unit called the ampere.
A continuous electric current of one ampere is defined to be one which deposits electrolytically 0.001118 of a gramme of silver per second from a neutral solution of silver nitrate.'
Another form of hot-wire ammeter is a modification of the electric thermometer originally invented by Sir W.
- Another large class of ammeters depend for their action upon the fact that an electric current create; an electric field round its conductor, which varies in strength from point to point, but is otherwise proportional to the current.
Direct reading equidivisional movable coil ammeters can be made in various portable forms, and are very much employed as laboratory instruments and also as ammeters for the measurement of large electric currents in electric generating stations.
- Instruments of the third class depend for their action on the fact discovered by Ampere, that mechanical forces exist between conductors carrying electric currents when those conductors occupy certain relative positions.
The great novelty in the ampere balances of Lord Kelvin was a joint or electric coupling, which is at once exceedingly flexible and yet capable of being constructed to carry with safety any desired current.
- For switchboard use i n Ammeter Kelvin & electric supply stations where space is valuable, James White instruments of the type called edgewise ammeters Ltd.
Swinburne, " Electric Light Measuring Instruments," Proc. Inst.
It is served by the Central Indiana, the Chicago & Eastern Illinois, the Evansville & Indianapolis and the Vandalia railways, and is connected with Indianapolis, Terre Haute and other cities by an interurban electric line.
It is served by the Pere Marquette Railroad, by steamboat lines to Chicago and other lake ports, and by electric lines connecting with Grand Rapids, Saugatuck, and the neighbouring summer resorts.
Holland is a grain and fruit shipping centre, and among its manufactures are furniture, leather, grist mill products, iron, beer, pickles, shoes, beet sugar, gelatine, biscuit (Holland rusk), electric and steam launches, and pianos.
It is served by the Chicago, Burlington & Quincy, the Chicago & North-Western, the Chicago, Milwaukee & St Paul, the Chicago, Milwaukee & Gary ("Rockford Route") and the Illinois Central railways, and is connected by interurban electric railway with Chicago and Freeport, Illinois, and Janesville, Wisconsin.
Carbon monosulphide, CS, is formed when a silent electric discharge is passed through a mixture of carbon bisulphide vapour and hydrogen or carbon monoxide (S.
It is served by the Lake Shore & Michigan Southern railway, and by the Cleveland & South-Western (electric) railway, which furnishes connexions directly with Cleveland and Elyria, and at the village of Wellington (about io m.
It fuses easily in the electric arc. It oxidizes superficially when heated, but fairly rapidly when ignited in an oxidizing blowpipe flame, forming a black smoke of the oxide.
Moissan (Comptes rendus, 1903, 1 37, p. 229) by the direct combination of the two elements in the electric furnace.
During the dark winter months work proceeds by the aid of electric light.
The village is served by the New York Central & Hudson River railway, by the Buffalo, Lockport & Rochester electric railway, and by the Erie Canal.
The city is well built, has many fine churches and good public buildings, street cars and electric lights.
About five years earlier the McKinley bridge was erected by the Illinois Traction Co., primarily to admit interurban electric trains.
It is served by the Chicago, Milwaukee & Saint Paul, the Chicago & North-Western, the Chicago, Rock Island & Pacific (which has repair shops here), and the Illinois Central railways, and by interurban electric lines.
south of the city; and Ponce de Leon Park, owned by an electric railway company and having mineral springs and a fine baseball ground.
and is served by an interurban electric line and by steamboat lines to Portland, Boston, Bangor, Bar Harbor and other coast ports.
Jersey City is served by several inter-urban electric railways and by the tunnels of the Hudson & Manhattan railroad company to Dey St.
Flexible tubing for electric wires (first made at Chelsea 1889) and art tiles are important products.
For example, the physicist determines the density, elasticity, hardness, electrical and thermal conductivity, thermal expansion, &c.; the chemist, on the other hand, investigates changes in composition, such as may be effected by an electric current, by heat, or when two or more substances are mixed.
When binary compounds, or compounds of two elements, are decomposed by an electric current, the two elements make their appearance at opposite poles.
But the difference between these two classes of elements is one of degree only, and they gradually merge into each other; moreover the electric relations of elements are not absolute, but vary according to the state of combination in which they exist, so that it is just as impossible to divide the elements into two classes according to this property as it is to separate them into two distinct classes of metals and non-metals.
Thus, the affinity of hydrogen and oxygen for each other is extremely powerful, much heat being developed by the combination of these two elements; when binary compounds of oxygen are decomposed by the electric current, the oxygen invariably appears at the positive pole, being negative to all other elements, but the hydrogen of hydrogen compounds is always disengaged at the negative pole.
One other instance may be given; the equation 2NH3=N2+3H2 represents the decomposition of ammonia gas into nitrogen and hydrogen gases by the electric spark, and it not only conveys the information that a certain relative weight of ammonia, consisting of certain relative weights of hydrogen and nitrogen, is broken up into certain relative weights of hydrogen and nitrogen, but also that the nitrogen will be contained in half the space which contained the ammonia, and that the volume of the hydrogen will be one and a half times as great as that of the original ammonia, so that in the decomposition of ammonia the volume becomes doubled.
Berzelius's investigation of the action of the electric current on salts clearly demonstrated the invaluable assistance that electrolysis could render to the isolator of elements; and the adoption of this method by Sir Humphry Davy for the analysis of the hydrates of the metals of the alkalis and alkaline earths, and the results which he thus achieved, established its potency.
Tantalum has in recent years been turned to economic service, being employed, in the same manner as tungsten, for the production of the filaments employed in incandescent electric lighting.
N"Ecv, to smell) observed in 1785 by Martin van Marum to be formed by the action of a silent electric discharge on the oxygen of the air; he showed it to be an allotropic modification of oxygen, a view subsequently confirmed by Marignac, Andrews and Soret.
when exposed to the action of light its electric conductivity increases.
Formerly the sparkand absorption-spectra were the sole methods available; a third method was introduced by Crookes, who submitted the oxides, or preferably the basic sulphates, to the action of a negative electric discharge in vacuo, and investigated the phosphorescence induced spectroscopically.
In quantitative analysis the methods can be subdivided into: (a) gravimetric, in which the constituent is precipitated either as a definite insoluble compound by the addition of certain reagents, or electrolytically, by the passage of an electric current; (b) volumetric, in which the volume of a reagent of a known strength which produces a certain definite reaction is measured; (c) colorimetric, in which the solution has a particular tint, which can be compared with solutions of known strengths.
The quantitative precipitation of metals by the electric current, although known to Michael Faraday, was not applied to analytical chemistry until O.
The ever-increasing importance of the electric current in metallurgy and chemical manufactures is making this method of great importance, and in some cases it has partially, if not wholly, superseded the older methods.
(7) Electrolytic. - This method consists in decomposing a solution of a salt of the metal by the electric current and weighing the metal deposited at the cathode.
The platinum is maintained at a bright red heat, either by a gas flame or by an electric furnace, and the vapour is passed over it by leading in a current of oxygen.
The converse is presented in the common electric cell.
yds., is provided with an electric bell communicating with the warder in the tower, heated by hot-air pipes, and lighted by day through a window on the outer wall of the rotunda, and from sunset till ten o'clock by electric light.
Hoosick Falls is served by the Boston & Maine Railroad, and is connected by electric railway with Bennington, Vermont, about 8 m.
Edmond Becquerel was associated with his father in much of his work, but he himself paid special attention to the study of light, investigating the photochemical effects and spectroscopic characters of solar radiation and the electric light, and the phenomena of phosphorescence, particularly as displayed by the sulphides and by compounds of uranium.
Lancaster is served by the Hocking Valley, the Columbus & Southern and the Cincinnati & Muskingum Valley (Pennsylvania Lines) railways, and by the electric line of the Scioto Valley Traction Company, which connects it with Columbus.
It is served by the Baltimore & Ohio South-Western, the Chicago & Alton, the Chicago, Peoria & St Louis, the Illinois Central, the Wabash, and the Cincinnati, Hamilton & Dayton railways, and by inter-urban electric lines.
from Villefranche), and on the main line between Marseilles and Mentone; it is also connected with Nice and Mentone by an electric tramway.
It is served by the Baltimore & Ohio and the Pennsylvania railways, and is connected by an electric line with Byesville (pop. in 1900, 1267), about 7 m.
From the landing-stage, by the customs house, roads lead to the Place Mehemet Ali, the centre of the life of the city and the starting-point of the electric tramways.
There are no steam railways, but an electric line connects South Hadley and South Hadley Falls with the New York, New Haven & Hartford and the Boston & Maine railways at Holyoke.
In August 1908 the mileage of all railways (including electric) in Cuba was 232 9.8 m.
More effective was the electric arc. In 1892 Sir W.
Mehner patented heating the oxides of silicon, boron or magnesium with coal or coke in an electric furnace, and then passing in nitrogen, which forms, with the metal liberated by the action of the carbon, a readily decomposable nitride.
Sodium nitrite, the most commonly used salt of the acid, is generally obtained by heating the nitrate with metallic lead; by heating sodium nitrate with sulphur and sodium hydroxide, the product then being fractionally crystallized;(Read, Holliday & Sons): 3NaNO 3 +S+2NaOH = Na2S04+3NaN02+H20; by oxidizing atmospheric nitrogen in an electric arc, keeping the gases above 300° C., until absorption in alkaline hydroxide solution is effected (German Pat.
Roanoke is served by the Virginian railway, by the main line and the Shenandoah and the Winston-Salem divisions of the Norfolk & Western railway, and by electric railway to Vinton and to Salem.
The city is served by the Lake Shore & Michigan Southern; the New York, Chicago & St Louis; the Cleveland, Cincinnati, Chicago & St Louis; the Pennsylvania; the Erie; the Baltimore & Ohio; and the Wheeling & Lake Erie railways; by steamboat lines to the principal ports on the Great Lakes; and by an extensive system of inter-urban electric lines.
A gas company, first incorporated in 1837, supplies the city as well as Llandaff and Penarth with gas, but the corporation also supplies electric power both for lighting and working the tramways, which were purchased from a private company in 1898.
It is served by the Southern Pacific railway, by the Oregon Electric line (to Portland), and by a steamship line to Portland.
It is served by the Boston & Maine and the Central Vermont railways, and by interurban electric railways to Northampton, Holyoke, Sunderland and Pelham.
The port is connected with Lima by two railways and an electric tramway, with Oroya by railway 138 m.
The docks are provided with gas and electric lights, 18 steam cranes for loading and discharging vessels, a triple line of railway and a supply of fresh water.
It is of modern growth, possessing a town hall, market hall, free library, technical school, pleasant park and recreation grounds, and an extensive system of electric tramways and light railways, connecting with Burnley and Colne.
An excellent service of electric trams interconnect the towns of Hamburg, Altona and the adjacent suburbs, and steamboats provide communication on the Elbe with the riparian towns and villages; and so with Blankenese and Harburg, with Stade, Gliickstadt and Cuxhaven.
Honolulu is served by the Oahu railway, by electric lines to the principal suburbs, and by steamship lines to San Francisco, Seattle, Vancouver, Manila, Salina Cruz (Mexico), Victoria, Sydney, and Chinese and Japanese ports.
There is a privately owned electric street car service in the city.
When the passage of an electric current through a substance is accompanied by definite chemical changes which are independent of the heating effects of the current, the process is known as electrolysis, and the substance is called an electrolyte.
As an example we may take the case of a solution of a salt such as copper sulphate in water, through which an electric current is passed between copper plates.
Alessandro Volta of Pavia discovered the electric battery in the year 1800, and thus placed the means of maintaining a steady electric current in the hands of investigators, who, before that date, had been restricted to the study of the isolated electric charges given by frictional electric machines.
Immediately on its discovery intense interest was aroused in the new invention, and the chemical effects of electric currents were speedily detected.
When an electric current flows round a circuit, there is no accumulation of electricity anywhere in the circuit, hence the current strength is everywhere the same, and we may picture the current as analogous to the flow of an incompressible fluid.
Similar relations were found to hold and the amounts of chemical change to be the same for the same electric transfer as in the case of solutions.
Since the electric forces are active throughout the whole solution, all the ions must come under its influence and therefore move, but their separation from the electrodes is determined by the electromotive force needed to liberate them.
Under the influence of an applied electric force, he imagined that the B part of the first molecule was liberated at the anode, and that the A part thus isolated united with the B part of the second molecule, which, in its turn, passed on its A to the B of the third molecule.
He pointed out that it followed that the electric forces did not cause the interchanges between the opposite parts of the dissolved molecules but only controlled their direction.
Interchanges must be supposed to go on whether a current passes or not, the function of the electric forces in electrolysis being merely to determine in what direction the parts of the molecules shall work their way through the liquid and to effect actual separation of these parts (or their secondary products) at the electrodes.
This result again indicates that the parts of the molecules are effectively separate from each other, the function of the electric forces being merely directive.
The opposite parts of an electrolyte, which work their way through the liquid under the action of the electric forces, were named by Faraday the ions - the travellers.
In some cases porous diaphragms have been employed; but such diaphragms introduce a new complication, for the liquid as a whole is pushed through them by the action of the current, the phenomenon being known as electric endosmose.
That a body carrying a positive electric charge should move against the direction of the electric intensity is contrary to all our notions of electric forces, and we are compelled to seek some other explanation.
If some of the anions, instead of being simple iodine ions represented chemically by the symbol I, are complex structures formed by the union of iodine with unaltered cadmium iodide - structures represented by some such chemical formula as I(CdI 2), the concentration of the solution round the anode would be increased by the passage of an electric current, and the phenomena observed would be explained.
Kohlrausch formulated a theory of electrolytic conduction based on the idea that, under the action of the electric forces, the oppositely charged ions moved in opposite directions through the liquid, carrying their charges with them.
If we eliminate the polarization at the electrodes, it can be shown that an electrolyte possesses a definite electric resistance and therefore a definite conductivity.
The details of the calculation are given in the article Electric conduction, § where also will be found an account of the methods which have been used to measure the velocities of many ions by direct visual observation.
The verification of Kohlrausch's theory of ionic velocity verifies also the view of electrolysis which regards the electric current as due to streams of ions moving in opposite directions through the liquid and carrying their opposite electric charges with them.
As we have seen, Grotthus imagined that it was the electric forces which sheared the ions past each other and loosened the chemical bonds holding the opposite parts of each dissolved molecule together.
Clausius extended to electrolysis the chemical ideas which looked on the opposite parts of the molecule as always changing partners independently of any electric force, and regarded the function of the current as merely directive.
That question can only be answered by examining whether or not the particles move in an electric field.
The ions are associated with very large electric charges, and, whatever their exact relations with those charges may be, it is certain that the energy of a system in such a state must be different from its energy when unelectrified.
Again, water, the best electrolytic solvent known, is also the body of the highest specific inductive capacity (dielectric constant), and this property, to whatever cause it may be due, will reduce the forces between electric charges in the neighbourhood, and may therefore enable two ions to separate.
The dissociation theory refers this to the action of electric charges carried by the free ions.
An explanation of the failure of the usual dilution law in these cases may be given if we remember that, while the electric forces between bodies like undissociated molecules, each associated with equal and opposite charges, will vary inversely as the fourth power of the distance, the forces between dissociated ions, each carrying one charge only, will be inversely proportional to the square of the distance.
But when zinc dissolves, the zinc ions carry their electric charges with them, and the liquid tends to become positively electrified.
The electric forces then soon stop further action unless an equivalent quantity of positive ions are removed from the solution.
During a small electric transfer through the cell, the external work done is Ee, where E is the electromotive force.
Thus, if L denote the heat corresponding with the chemical changes associated with unit electric transfer, Le will be the heat corresponding with an electric transfer e, and will also be equal to the change in internal energy of the cell.
This process will go on until the simultaneous separation of electric charges produces an electrostatic force strong enough to prevent further separation of ions.
We can therefore calculate the rate at which the salt as a whole will diffuse by examining the conditions for a steady transfer, in which the ions diffuse at an equal rate, the faster one being restrained and the slower one urged forward by the electric forces.
The electric forces set up tend to prevent further separation, and finally a state of equilibrium is reached, when no 1 Zeits.
Our views of the nature of the ions of electrolytes have been extended by the application of the ideas of the relations between matter and electricity obtained by the study of electric conduction through gases.
An electric current consists of a moving stream of electrons.
It is at the intersection of two branches of the Boston & Maine railway, and is served by several interurban electric lines.
22 a rapidly transformed into a modern European town, with wide streets, electric tramways and electric lighting.
An electric line extends to Grass Valley (pop. in 1900, 47 1 9), 4 m.
ELECTROPLATING, the art of depositing metals by the electric current.
In the article Electrolysis it is shown how the passage of an electric current through a solution containing metallic ions involves the deposition of the metal on the cathode.
It is served by the Lehigh Valley and the New York Central & Hudson River railways, and by inter-urban electric lines.
An extensive service of electric tramways is maintained.
The municipality owns and operates the water-works (the water-supply being drawn from the Penobscot by the Holly system) and an electric-lighting plant; there is also a large electric plant for generation of electricity for power and for commercial lighting, and in Bangor and the vicinity there were in 1908 about 60 m.
of electric street-railway.
In 1836 a railway from Bangor to Old Town was completed; this was the first railway in the state; Bangor had, also, the first electric street-railway in Maine (1889), and one of the first iron steamships built in America ran to this port and was named "Bangor."
Bowling Green is served by the Cincinnati, Hamilton & Dayton and the Toledo & Ohio Central railways, and by the Toledo Urban & Interurban and the Lake Erie, Bowling Green & Napoleon electric lines, the former extending from Toledo to Dayton.
It is served by the New York, New Haven & Hartford railroad and by interurban electric railways.
It is served by the Grand Trunk and the Pontiac, Oxford & Northern railways (being the southern terminus of the latter), and by the Detroit & Pontiac and the North-Western electric inter-urban lines.
A system of electric tramways connects the town with its principal suburbs.
The municipality maintains an electric tram service.
Miscellaneous Effects of Magnetization: Electric Conductivity - Hall Effect - Electro-Thermal Relations - Thermoelectric Quality - Elasticity - Chemical and Voltaic Effects.
A wire carrying an electric current is surrounded by a magnetic field, and if the wire is bent into the form of an elongated coil or spiral, a field having certain very useful qualities is generated in the interior.
In the internal field of a long coil of wire carrying an electric current, the lines of force are, except near the ends, parallel to the axis of the coil, and it is chiefly for this reason that the field due to a coil is particularly well adapted for inductively magnetizing iron and steel.
Again, a steel wire through which an electric current has been passed will be magnetized, but so long as it is free from stress it will give no evidence of magnetization; if, however, the wire is twisted, poles will be developed at the two ends, for reasons which will be explained later.
The dimensions of a piece of iron, for example, its elasticity, its thermo-electric power and its electric conductivity are all changed under the influence of magnetism.
A magnetic field is generally due either to a conductor carrying an electric current or to the poles of a magnet.
Magnetic induction, like other fluxes such as electrical, thermal or fluid currents, is defined with reference to an area; it satisfies the same conditions of continuity as the electric current does, and in isotropic media it depends on the magnetic force just as the electric current depends on the electromotive force.
The circulation of magnetic induction or flux through magnetic and non-magnetic substances, such as iron and air, is in many respects analogous to that of an electric current through good and bad conductors.
The total magnetic induction or flux corresponds to the current of electricity (practically measured in amperes); the induction or flux density B to the density of the current (number of amperes to the square centimetre of section); the magnetic permeability to the specific electric conductivity; and the line integral of the magnetic force, sometimes called the magnetomotive force, to the electro-motive force in the circuit.
The principal points of difference are that (I) the magnetic permeability, unlike the electric conductivity, which is independent of the strength of the current, is not in general constant; (2) there is no perfect insulator for magnetic induction, which will pass more or less freely through all known substances.
In the middle part of a rod which has a length of 400 or 500 diameters the effect of the ends is insensible; but for many experiments the condition of endlessness may be best secured by giving the metal the shape of a ring of uniform section, the magnetic field being produced by an electric current through a coil of wire evenly wound round the ring.
- An electric current i flowing uniformly through a cylindrical wire whose radius is a produces inside the wire a magnetic field of which the lines of force are concentric circles around the axis of the wire.
Rowland and others have used an earth coil for calibrating the galvanometer, a known change of induction through the coil being produced by turning it over in the earth's magnetic field, but for several reasons it is preferable to employ an electric current as the source of a known induction.
Fleming, Magnets and Electric Currents, p. 193) are shown three very different types of hysteresis curves, characteristic of the special qualities of the metals from which they were respectively obtained.
It is, of course, true for permanent magnets, where H = o, since then F = 27rI 2; but if the magnetization is due to electric currents, the formula is only applicable in the special case when the mutual action of the two magnets upon one another is supplemented by the electromagnetic attraction between separate magnetizing coils rigidly attached to them.2 The traction method was first employed by S.
If a coil of insulated wire is suspended so that it is in stable equilibrium when its plane is parallel to the direction of a magnetic field, the transmission of a known electric current through the coil will cause it to be deflected through an angle which is a function of the field intensity.
- The most generally convenient arrangement for producing such magnetic fields as are required for experimental purposes is undoubtedly a coil of wire through which an electric current can be caused to flow.
Knott on magnetic twist, which will be referred to later, led him to form the conclusion that in an iron wire carrying an electric current the magnetic elongation would be increased.
The most interesting of his discoveries, now generally known as the " Wiedemann effect," is the following: If we magnetize longitudinally a straight wire which is fixed at one end and free at the other, and then pass an electric current through the wire (or first pass the current and then magnetize), the free end of the wire will twist in a certain direction depending upon circumstances: if the wire is of iron, and is magnetized (with a moderate force) so that its free end has north polarity, while the current through it passes from the fixed to the free end, then the free end as seen from the fixed end will twist in the direction of the hands of a watch; if either the magnetization or the current is reversed, the direction of the twist will be reversed.
Hall Efect.-If an electric current is passed along a strip of thin metal, and the two points at opposite ends of an equipotential line are connected with a galvanometer, its needle will of course not be deflected.
Rev., 1904, 18, 370) in the electric arc.
Electro-Thermal Relations.-The Hall electromotive force is only one of several so-called " galvano-magnetic effects " which are observed when a magnetic field acts normally upon a thin plate of metal traversed by an electric current.
A transverse difference of electric potential (Hall effect).
electric potential (Nernst effect).
Longitudinal change of electric conductivity.
electric potential.3 If in the annexed diagram AB CD represents the metallic plate through which the current of electricity or heat flows in the E.
The fact being established that magnetism is essentially a molecular phenomenon, the next step is to inquire what is the constitution of a magnetic molecule, and why it is that some molecules are ferromagnetic, others paramagnetic, and others again diamagnetic. The best known of the explanations that have been proposed depend upon the magnetic action of an electric current.
Ferromagnetism was explained by Ampere on the hypothesis that the magnetization of the molecule is due to an electric current constantly circulating within it.
To account for diamagnetism, Weber supposed that there exist within the molecules of diamagnetic substances certain channels around which an electric current can circulate without any resistance.
The creation of an external magnetic field H will, in accordance with Lenz's law, induce in the molecule an electric current so directed that the magnetization of the equivalent magnet is opposed to the direction of the field.
There are strong reasons for believing that magnetism is a phenomenon involving rotation, and as early as 1876 Rowland, carrying out an experiment which had been proposed by Maxwell, showed that a revolving electric charge produced the same magnetic effects as a current.
Thomson and others once more brought the conception of moving electric charges into prominence.
The process of electric conduction in metals consists in the movement of detached electrons, and many other phenomena, both electrical and thermal, can be more or less completely explained by their agency.
The question whether a corpuscle actually has a material gravitating nucleus is undecided, but there are strong reasons for believing that its mass is entirely due to the electric charge.
C. Oersted 6 that a magnet placed near a wire carrying an electric current tended to set itself at right angles to the wire, a phenomenon which indicated that the current was surrounded by a magnetic field.
Ampere's experimental and theoretical investigation of the mutual action of electric currents, and of the equivalence of a closed circuit to a polar magnet, the latter suggesting his celebrated hypothesis that molecular currents were the cause of magnetism.
Arago 8 succeeded in magnetizing a piece of iron by the electric current, and in 1825 W.
Maxwell explained electric and magnetic forces, not by the action at a distance assumed by the earlier mathematicians, but by stresses in a medium filling all space, and possessing qualities like those attributed to the old luminiferous ether.
Moissan by reducing the oxide with carbon in the electric furnace (the product obtained always contains from 2-3% of combined carbon), and by H.
All the large cities of Brazil are liberally provided with tramways, those of the city of Sao Paulo, where electric traction is used, being noticeably good.
Modern industrial development in some of the states has greatly increased the importation of machinery, electric supplies, materials for construction, coal, &c. Kerosene oil also figures among the principal imports, and beef cattle are imported for consumption by some cities.
It is served by the Grand Trunk and the Pere Marquette railways, and by an electric line, the Detroit United railway, connecting with Detroit.
The corporation has acquired the gas-works, the cable tramways (leased to a company), the electric lighting of the streets, and the water-supply from the Pentlands (reinforced by additional sources in the Moorfoot Hills and Talla Water).
long and equipped with electric light, stationary and travelling hydraulic cranes, machinery for meat freezing, and large sheds for storing corn and wool.
The gas and electric lighting is in the hands of private firms. The administration of the park, the city improvements and the water and sewerage departments have been handed over to boards and trusts.
These suburbs are connected with the city, some by railway, some by steam, cable and electric tramways, and others by ferry across Port Jackson.
C. Oersted (1777-1851) had shown that a magnetic needle is deflected by an electric current, he attempted, in the laboratory of the Royal Institution in the presence of Humphry Davy, to convert that deflection into a continuous rotation, and also to obtain the reciprocal effect of a current rotating round a magnet.
The city is served by the Louisville & Nashville, the Nashville, Chattanooga & St Louis, and the Western & Atlantic railways, and is connected with Atlanta by an electric line.
It is served by the Pennsylvania, the Baltimore & Ohio, and the Wheeling & Lake Erie railways, and is connected by an interurban electric system with all the important cities and towns within a radius of 50 m.
It is served by the Boston & Maine railroad and by electric railways to Andover, Boston, Lowell, Haverhill and Salem, Massachusetts, and to Nashua and Salem, New Hampshire.
rend., 1896, 122, p. '088), in which the oxide is heated with sugar charcoal in the electric furnace.
There is ample water power, and there are manufactures of paper, sash and blinds, fibre, &c. From a dam here power is derived for the General Electric Company at Schenectady.
(2) A solution of pure stannous chloride in very dilute hydrochloric acid is reduced with an electric current.
Iquique is a city of much commercial importance and is provided with banks, substantial business houses, newspapers, clubs, schools, railways, tramways, electric lights, telephone lines, and steamship and cable communication with the outside world.
It is served by the Chicago, Cincinnati & Louisville, the Grand Rapids & Indiana and the Pittsburg, Cincinnati, Chicago & St Louis railways, and by the Terre Haute, Indianapolis & Eastern and the Ohio electric interurban railways.
There are a number of electric plants, three of which use water power, one at El Encantado, 10 m..
It is served by the Erie, the Lehigh Valley, the Delaware, Lackawanna & Western, the Central of New Jersey, the Delaware & Hudson, and the Lackawanna & Wyoming Valley railways; there is an electric railway from Pittston to Scranton, and a belt-line electric railway connects Pittston with Avoca, Nanticoke, Plymouth and Wilkes-Barre.
The town is governed by a municipality, which since 1903 has acquired control of the sanitary service, water supply, electric lighting and tramways.
It is served by the Chicago Burlington & Quincy railroad and by the Galesburg & Kewanee Electric railway.
It is served by the Michigan Central, the Lake Shore & Michigan Southern, the Grand Rapids & Indiana, the Kalamazoo Lake Shore & Chicago, and the Chicago Kalamazoo & Saginaw railways, and by interurban electric lines.
The city is served by the Gulf, Colorado & Santa Fe, and the Missouri, Kansas, & Texas railways, and by an interurban electric railway.
It is served by the Maine Central railway, by steamboat lines to Boston, and by inter-urban electric railway.
As regards the generation of electric energy, by pointing out defects of design in the dynamo as it existed about 1878, and showing.
Again, as regards the distribution of the current, he took a leading part in the development of the three-wire system and the closed-circuit transformer, while electric traction had to thank him for the series-parallel method of working motors.
The Underground Electric Railways Company, which acquired a controlling influence over these concerns, undertook the construction of a great power station at Chelsea; while the Metropolitan Company, which had fallen into line with the District (not without dispute over the system of electrification to be adopted) erected a station at Neasden on the Aylesbury branch.
Electric traction was gradually introduced on the Metropolitan and the District lines in 1906.
Deeplevel electric railways (" tubes "), communicating with the surface by lifts, were already familiar in London.
Both electric and horse traction are used; the latter, however, has been in great part displaced by the former.
The Metropolitan Board of Works, and the commissioners of sewers in the City, began experiments with electric light.
At the close of the 19th and the beginning of the 20th century a large number of electric light companies came into existence, and some of the metropolitan borough councils, and local authorities within Greater London, also undertook the supply.
Howth is connected with the capital by electric tramway, besides the railway, and another tramway encircles the hill.
Steam locomotives have been largely superseded by compressed air or electric locomotives.
Electric locomotives usually work on the trolley system, though a few storage battery locomotives have been successfully employed.
Electric and compressed air locomotives are durable, easily operated, and can be built to run under the low roofs of thin veins.
Electric locomotives are in general more economical then either steam or compressed air.
For heavy gradients rope haulage has no rival, though for moderate grades it is often advantageously replaced by electric and compressed air haulage.
King patented filament electric lamps exhausted by the same methods.
Patten in 1824; whilst in 1881 Rankine Kennedy resuscitated the idea for the purpose of exhausting filament electric lamps.
Albany is a terminus of the New York Central & Hudson River, the Delaware & Hudson and the West Shore railways, and is also served by the Boston & Maine railway, by the Erie and Champlain canals (being a terminus of each), by steamboat lines on the Hudson river and by several inter-urban electric railways connecting with neighbouring cities.
Among the educational institutions are the Albany Medical College (1839) and the Albany Law School (1851), both incorporated since 1873 with the Union University, the Collegiate Department of which is at Schenectady; the Albany College of Pharmacy (1881), also part of Union University; the Albany Academy (1813), in which Joseph Henry, while a member of the faculty, perfected in 1826-1832 the electro-magnet and began his work on the electric telegraph; the Albany Academy for Girls, founded in 1814 as the Albany Female Academy (name changed in 1906); and a State Normal College (1890), with a Model School.
It is served by the Louisville & Nashville, and the Chesapeake & Ohio railways, and by electric lines to Covington, Cincinnati, Bellevue, Fort Thomas and Dayton.
Calcium cyanamide has assumed importance in agriculture since the discovery of its economic production in the electric furnace, wherein calcium carbide takes up nitrogen from the atmosphere to form the cyanamide with the simultaneous liberation of carbon.
Electrical furnaces have not as yet been employed for ordinary glass-making on a commercial scale, but the electrical plants which have been erected for melting and moulding quartz suggest the possibility of electric heating being employed for the manufacture of glass.
The spindles of cutting wheels are driven by steam or electric power.
The processes employed in the manufacture of the glass bulbs for incandescent electric lamps, are similar to the old- FIG.
A somewhat impure silicon (containing 90-98% of the element) is made by the Carborundum Company of Niagara Falls (United States Patents 745 122 and 842273, 1908) by heating coke and sand in an electric furnace.
The specific heat varies with the temperature, from 0.136 at -39° C. to 0.2029 at 232° C. Silicon distils readily at the temperature of the electric furnace.
Silicon hydride, SiH4, is obtained in an impure condition, as a spontaneously inflammable gas, by decomposing magnesium silicide with hydrochloric acid, or by the direct union of silicon and hydrogen in the electric arc. In the pure state it may be prepared by decomposing ethyl silicoformate in the presence of sodium (C. Friedel and A.
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