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to boil water or cook food. As the maximum heat is generated at the lower surface, the plate is pierced with air holes; the top of the magnet poles are also protected from heating. Mr. Guttmann shows an electric stove lined with brick, any chamber or plate of which can be immediately heated up to any desired temperature by turning and adjusting the switches.

Chislehurst.—The Chislehurst Parochial Committee on Monday again discussed the proposal of the Electric Lighting Supply Company, with respect to obtaining a provisional order. If the order is obtained several large property owners will fix the electric light to the houses owned by them. Mr. R. G. Mullen said if the company were allowed to obtain a provisional order they would have a monopoly throughout the parish. This had been the view which had actuated the Bromley Local Board, of which he was clerk, in obtaining the powers for themselves, in order that they should have some control over the lighting of their district. If the local authority applied there would be an expense of about £100 in printing, and about £50 in House of Commons expenses. That would be all if the application were not opposed, and their own officials acted as in the case at Bromley. The consideration of the matter was adjourned until the next monthly meeting, in order that every member might be present. An agitation has commenced at Sidcup for the electric light, and as Sidcup is a town carved out of the parishes of Chislehurst, Foots Cray, Bexley, and Eltham, it comes under the same central body-the Bromley Rural Sanitary Authority-who will have to obtain the provisional order, should the local committees decide in favour of so doing.

Plymouth. At the Plymouth Town Council meeting last week, Mr. F. W. Harris moved the adoption of the report of the Works Committee, which contained the following amongst other recommendations: "That Messrs. F. W. Harris, Cuming, Bray, Lapthorn, Kerswill, and Lethbridge be appointed a sub-committee to confer with the engineer of the Devon and Cornwall Electric Lighting Company with reference to the lighting of the borough with electric light. That tenders be invited for the lighting of the borough." In reply to questions, Mr. Harris said the committee would be glad of any assistance from the Electric Lighting Committee in the matter of the arrangements with the Devon and Cornwall Electric Lighting Company. He understood that another communication had been received from the company, and that it, together with further information from the surveyor, would be laid before the committee. A correspondent to the Western Morning News suggests the utilisation of the water power in the town. He points out that there is a good fall at Drake'splace, at the King's Mill site, and the old Providence Mill site, all belonging to the town. There need be no difficulty at all in piping it to convey the water to the sites. The town would thus save the cost of steam power, and as the plant would only be worked by night, waste water not required by the inhabitants would be used, which would thus help to lighten the rates.

Derby Industrial Exhibition.-During the past month an industrial exhibition has been held at the Drill Hall, Derby, where electrical appliances were exhibited by Messrs. John Davis and Son, of Derby, and the National Telephone Company. In the engine-room at the entrance were some four or five engines at work, and here Messrs. Davis exhibited an 18-unit compound-wound dynamo, driven by a "Trent" gas engine; this dynamo was used for lighting the hall and stage with incandescent lamps of from 16 c.p. to 500 c.p. A 24-unit dynamo, driven by another engine, was used to work a motor for an automatic grain-weigher, an engraving machine, and a

ventilating fan placed in the hall; the whole_plant worked perfectly from the beginning. On Messrs. Davis's stand in the hall were exhibited a large variety of tele phones, mining bells, and Keys' portable primary and secondary lamps (one of which for use in mines gives 1 c.p. for 10 hours and weighs 3lb.), and an extensive assortment of their well-known dust-proof fittings for mines, iron works, ships, etc. They also showed their new electric workman's time check, worked by hand or by a clock from the foreman's office, and numerous other handy applications of electricity. Their exhibits as a whole comprised the greater number of the departments of electrical engineering, and has obtained the gold medal, as was the case at the mining exhibition of last year.

Electric Street Cars.-Mr. Walter M. Galbraith, writing to the Glasgow Herald upon the subject of the introduction of electric cars into that city, says, with reference to their entensive use in America, "I visited the States in spring, travelling right across the Continent to the Pacific, and I had ample opportunity of testing and comparing the American system of street cars with our own, and it requires no very practical electrician to see that we are about as far behind 'Brother Jonathan' in this respect as we possibly can be. The objection has been raised that electric cars are not adapted for steep gradients, such as Renfield-street or New City-road, in Glasgow. But this is quite a mistake. I spent a Sunday in Tacoma, which is built on a very steep slope, most of the streets being quite as precipitous as those leading up to Garnethill, and I watched with great interest the electric car going up and down the steep incline, and no one but myself seemed to be aware that there was any danger, as there was absolutely none beyond that which existed in my own imagination. As regards speed, this can be regulated to the district and in accordance with the traffic, but it must be apparent to all that it is an immense advantage to be able to run the cars rapidly, say, up to a speed of eight to ten miles an hour, if required, and not be, as at present, bound down to the orthodox four miles an hour, with something considerably less when the car is heavily loaded. In Victoria, B.C., the electric cars run right into the country, and go at a rate which allows gentlemen to go home at midday, 10 minutes being sufficient to take them to their destination. The car runs out to Esquimault, so that the evening can be spent in the country, far away from all temptation, and still you can be landed at your own door without experiencing the fatigue and excitement connected with railway travelling." Another correspondent suggests that an exhaustive report should be obtained on this subject from Sir W. Thomson and the president of the Institution of Engineers in Glasgow.

Birmingham Town Hall.—An installation of some importance in Birmingham, that of the Town Hall, has just been put to a preliminary trial in the presence of the committeemen, with satisfactory results. The Birmingham Town Hall was one of the first public places wherein the electric light was installed in the early days, but its prohibitive cost only allowed it to be used for demonstrative purposes. The present lighting has been carried out by Messrs. Winfield, from specifications by Mr. Henry Lea, M.I.C.E., electrical adviser to the Town Council, the current being obtained from the mains of the Birmingham Electric Supply Company. The lamps are suspended from the ceiling on large electroliers, principally two central pendants, one of 30 and the other of 24 incandescent lamps of 32 c.p. These supply sufficient light for ordinary occasions, but for fuller and more brilliant illumination they are supplemented by 16 smaller pendants of eight or 10 lamps each. A series of single lamps are also arranged under the galleries. The total number

of lamps in the great hall is 224, equal to 6,880 c.p. The pendants, of classical design by Messrs. Winfield, carry frosted globes without shades. Each electrolier is suspended by steel wires in such a manner that it can be readily lowered for cleaning, repairs, or alteration in the number of lamps. They are hung 36ft. above the level of the floor. The installation extends to every part of the building, in all containing 425 lamps, of which 273 are of 32 c.p. and the remainder of 16 c.p. The size of cables adopted is very large, three pairs consisting of 61 strands of No. 11 wire, measuring outside insulation about 2in. diameter. This large size was adopted to keep the loss in the building to within two volts, of which volt only is allowed in the service mains. The main fuses and switches were supplied by the Electric Supply Company; the wiring was done by the Midland Electric Lighting Company, as sub contractors to Messrs. Winfield. The total cost of the installation is £1,500.

Electric Resistance of Metals.-M. Le Chatelier

has proposed to characterise the varying molecular state of metals by the value of their electric resistance, and to determine by the same method the exact temperatures at which they pass from one state into another. At the point of transformation the resistance does not suddenly change, as does the volume, the latent heat, and the greater number of physical properties: the law of increment alone experiences a sudden change, giving an angular point on the the representative curve. For iron and nickel the resistance, cold, and the law of increment are identical up to 340deg. C. At this temperature a sharp angle announces the well-known transformation of nickel. For iron, the corresponding transformation takes place at 850deg. C. Above each of these temperatures the curves of resistance are rectilinear and parallel. The transformation at 850deg. also takes place in carbon steel and silicium steel. This affords evidence in favour of the cellular theory of M. Osmond. The fixity of the point of transformation implies, in fact, the simple mechanical juxtaposition of pure iron with the carbide or silicide. In nickel steels, on the other hand, the transformation of the two metals takes place at a determined temperature for each alloy, intermediate between 850deg. and 340deg. For the various alloys tested this temperature varies between 400deg. and 600deg. C. Carbon steels gave a second angular point at the temperature of 730deg. C., corresponding to the transformation known under the name of recalescence. This point remains the same when

the amount of carbon varies. The curves of electric resist

ance have not given any other indication of molecular transformation of iron and its alloys. It might not be impossible, however, that the loss of magnetic properties of iron and steel which, according to the experiment of M. Ledeboer and Dr. Hopkinson, take place at 760deg, correspond to a third molecular transformation, which would be the point ap, in M. Osmond's theory. This transformation may be prevented by the tempering, which is not the case, however, with the transformation of 85Cdeg.

Blakey-Emmott Catalogue.-Halifax possesses, in the shape of Messrs. Blakey, Emmott, and Co., a firm whose electrical works are of considerable and growing importance. We are just in receipt of their catalogue, and from it gain some interesting details of the extent of the works. These are shown in one of the illustrations in the catalogue, and cover a total area of 1 acres, comprising a prinicipal works of seven floors and several outbuildings, in which all branches of the trade is carried on. The catalogue illustrates their well-known single-magnet "Blakey-Emmott" dynamo, made for all sizes up to 30,000 watts capacity. Above this size they are made of the four-pole type,

of

The armatures on the two-pole machines are Gramme type, and in the four-pole machines drum type, built up charcoal iron discs carefully insulated. The cores are insulated with mica before being wound. The winding consists of one layer only. These dynamos make efficient motors and develop approximately the same brake horse-power as required to drive them as dynamos. The Blakey-Emmott alternator is a handsome machine, consisting of a huge ring (in two parts) with 14 internally pointing poles. The armature is simply a ring built up of iron discs, and mounted on a metal spider axle. Upon the surface of this armature the conductors are laid, there being no internal wires or crossings. The insulation is of mica, and the brushes are of carbon, on solid collector rings. The magnets are separately excited in the usual way. These alternators work well in parallel, and are usually made for 100 cycles per second. "Blakey-Emmott " transformers are shown -2,500 The illustration of a mudel small central station plant already carried out, is given with particulars. Special combinations of engine and dynamo for restricted space, as on shipboard, are shown with vertical engine of moderate speed with slowspeed dynamo. Switches, main fuses, differential arc lamps, potential and current meters, Oulton and Edmondson's meters, and the "Blakey-Emmott" gas or petroleum engine also appears in the catalogue, from whence it is seen that the firm are in a position to supply entire electric light and power requirements of their own manufacture.

to 10 volts.

Concentric Wiring in Liverpool.-An important installation, in which Andrews's system of concentric wiring is used, has just been completed at the Waterloo Grain Warehouses, Liverpool, belonging to the Mersey Docks and Harbour Board. This system, which is already well known to most of our readers, has as its important feature the outer, or return conductor, made of iron uninsulated, forming a substantial protection to the insulation of the inner conductor of copper, and making, with the solid brass cases of the cut-outs, switches, etc., an unbroken conductor throughout. Switches and cut-outs act only on the centre wire. No wood casing whatever is required. The installation will be a favourable opportunity to demonstrate the merits of the system. The Waterloo Warehouses consist of three six-storey blocks, 80ft. wide, built along three sides of the Waterloo Corn Dock. The middle block is 180ft. long, and the side blocks are each 650ft. At intervals along the centre of each block hatchways for hoisting purposes reach from the quay level to the top of the building, and upon each of these a branch wire securely fixed in an angle-iron is carried, and conveys current to two sockets at each floor. Long lengths of steel-armoured flexible wire provided with couplings to fit these sockets are used for attaching the lamps. Each flexible wire supplies one 50-c.p. lamp, which can thus be moved about the room and placed in the most convenient position for working by, and a number of lamps can be grouped wherever a strong light is required. Similar sockets and flexible leads are arranged for carrying lights down into the holds of vessels lying in the dock, so that the trimmers on board may also have plenty of light for their work. The dynamo in connection with this installation is of Messrs. W. T. Goolden and Co.'s well-known make; it is driven by a belt from an engine of the inverted vertical marine type, steam being supplied by the main boilers used for the hydraulic system on the Dock Estate. The installation has been carried out to the specification of Mr. G. F. Lyster, the dock engineer, by Messrs. J. D. F. Andrews and Co., 41 and 42, Parliament-street, London, S. W., with the assistance of Mr. W. S. Boult, A.M.1.C.E., 60, Castle-street, Liverpool, their sole agent. for Lancashire and Cheshire.

SOME ELECTRICAL WORDS.

A very fair idea of the rise and progress of a science may be gathered from a study of the technical terms which have been used from time to time to explain the various phenomena, or for the purpose of setting forth new theories. Should anyone be disposed to make such an attempt in regard to electricity, he will find the material ready to his hand in the recently-issued part (E-Every) of the "New English Dictionary on Historical Principles," a monumental work now in course of publication by the Oxford University Press. As there may be some who are unacquainted with this modern "Johnson," it is perhaps necessary to say that it is based, as the title sets forth, on strictly "historical principles." It is true that the definitions are generally in the editor's own words, but they are little more than a summing-up of the evidence furnished by quotations from authors of acknowledged repute, and as full references are always given, the reader can verify them for himself and obtain further information if he wishes for it.

The word "" electricity" and the various compounds under "electro" occupy more than ten closely printed columns of small type, enough to more than fill an entire number of the Electrical Engineer. We do not advocate any radical reform in scientific nomenclature, but it is curious to observe what a vast superstructure has been built upon a foundation which is, logically speaking, utterly insecure. Every text-book tells us that "electric is derived from a Greek word signifying "amber," that substance when rubbed developing electricity. But who thinks of amber in connection with the electrical science of the present day? The modern Latin word seems to have been first used by Gilbert, in 1600, in his treatise "De Magnete," and the earliest instance of its use in English is in Sir Thomas Browne's "Vulgar Errours" (1646). For "electrical" there is an earlier authority in Carpenter's "Gegoraphy Delineated" (1635). The editor notices the somewhat arbitrary uses of the words "electric" and "electrical," which are precisely synonymous, although we should not expect to be asked "Have you bought any electric books lately?" nor do we usually speak of the "electrical light." Proceeding in alphabetical order we come upon "electricalness," a word we never met with before. The only authority for it is Bailey's Dictionary (1736), but we doubt if the word was ever actually used. We were rather surprised to learn that "electrician" dates as far back as 1751, when we find Franklin saying in the Philosophical Transactions "I have not heard that any of your European do it"-words which somehow or other have a familiar sound, as if we had heard them only the other day. Electricity" is a long article, the earliest quotation being again from Sir Thomas Browne's "Vulgar Errours" (1646). The Philosophical Transactions furnish many examples, and the editor points out that the term "electric fluid survives in popular language, and that "positive" and "negative," which we also inherit from Franklin's theory, are still in

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"Electric light,” in its modern restricted sense, makes its first appearance in 1843, as the heading of a paragraph in the Mechanics' Magazine, "Electric Light a Substitute for Gas." The Daily News is responsible for "a beautiful electric-lighted clock." We come next upon the uncouth word" Electricology," which is the title of a work on electricity, written in 1746 by one R. Turner. Bennet, a wellknown electrician of the last century is credited with a proposal for "an electrico-meteorological diary." "Electrify" seems to be Franklin's word, and dates from 1747.

The compounds of "electro" number about a hundred, and although we are not disposed to set up as purists we cannot avoid the observation that many of them are nothing better than base coin. This remark, however, must not be understood as attributing blame to the editor for retaining them. This is no "Dictionnaire de l'Académie" which is to serve as a standard of propriety of language, but it includes everything, whether good, bad, or indifferent. Faraday's words are generally referred to their original source, and we should have thought that "electrolysis" was due to

him, but Todd's "Cyclopædia of Anatomy" is the earliest. authority given. The word is said to have two meanings: (1) chemical decomposition by galvanic action, and (2) the name of a branch of science. This seems to us to be unnecessary. The word "electro-magnet " only goes back to 1831, which is the date of a paper in Silliman's Journal. "Electro-magnetic" dates from 1823, and 1823, and "electromagnetism" from 1828. We have to note some deficiencies here, and Oersted's papers in the Annals of Philosophy for October and November, 1820, would have furnished an earlier quotation for "electro-magnetic," whilst Faraday's "Historical Sketch of Electro-magnetism" in the Annals for September, 1821, shows that the word is at least seven years older than stated in the Dictionary. It might also have been worth noting that "electro-magnet meant originally a solenoid, such as the little apparatus known as De la Rive's "floating battery."

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As the Dictionary takes account of words only, some confusion occasionally arises by reason of the same word being used to denote different things. For instance, under "Electrometer" we have a reference to Lane's apparatus known by this name described in the Philosophical Transactions for 1766, where the contriver suggests that his instrument " may not improperly be called an electrometer." Under the same heading there are other quotations which obviously refer to " electroscopes," as we now call them, such as Bennet's gold-leaf electroscope. One has to bear this change of name in mind to account for the fact that no authority earlier than 1824 has been found for the word "electroscope."

Under "electro-motive" our contemporary the Engineer is quoted in support of the use of this word as a substantive, in the sense of a locomotive engine worked by electricity. This is very sad, and should be rigorously put down along with "electrolier," though we have endured "gaselier" for so long that we fear this last abortion cannot be refused admission into our vocabulary.

The striking character of electrical phenomena seems to have taken firm hold on the popular imagination, and we find accordingly that the technical terms of the science have been largely adopted by general writers in a figurative or metaphorical sense. As early as 1752 Lord Chesterfield writes to his son "you will not be so agreeably electrified as you were at Manheim." Coleridge (1793) has these lines:

The electric flash that from the melting eye,

Darts the fond question or the soft reply. The editors do not often "drop into poetry" or they might have given Clerk Maxwell's poetical rendering of Faraday's discovery. It is so good that it will always bear quotation : Around the magnet Faraday

Is sure that Volta's lightnings play;

But how to draw them from the wire !
He takes a lesson from the heart.
'Tis when we meet, 'tis when we part,
Breaks forth th' electric fire!

Here is a striking quotation from Carlyle's "Sartor Resartus": "Wait a little till the entire nation is in an electric state; till your whole vital electricity. . . is cut into two isolated portions of Positive and Negative; of Money and Hunger." Max Müller speaks of "the electric light of Comparative Philology."

We have by no means exhausted the interest of this part of the dictionary; and those who are in the habit of occasionally thinking of the words they use daily, as they sometimes scrutinise the image and superscription of a current coin, will find much that is suggestive. As we have already remarked, theories now discarded have left their mark on the language of to-day, and it is more than probable that the words we now invent, and which wo think are altogether admirable, will in turn become meaningless.

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as the dynamo must be "run up" to this increased voltage, although only a portion of the current generated may be used for charging, the remainder being required for the lamps at the normal voltage.

We illustrate a neat arrangement devised by Messrs. W. B. Sisling and W. H. Scott, which seems to overcome this difficulty, and has several features which ought to prove advantageous in a private installation. The arrangement may be described as a compound dynamo, with a small supplementary winding on its armature connected to an extra commutator, which gives a voltage usually about one quarter of that given by the main commutator. A branch is taken from the main circuit and connected so that the extra commutator raises its voltage by about 25 per cent. This forms the charging circuit. The dynamo can thus be driven at constant speed, and will supply constant voltage to the lamps from its main circuit undisturbed by the increasing voltage from the cells during charging. The whole of the cells can be charged and a large current supplied to the lamps at the same time, as this does not pass through the regulating cells. The charging can therefore be accomplished during the hours of lighting, instead of the dynamo having to be run specially during the day.

The contract between the Corporation of Dublin and the Electric Engineering Company of Ireland was completed on Saturday. The contract provides for the lighting by electricity of O'Connell-street, Capel-street, Henry-street, Mary street, Parliament-street, Dame-street, College-green, College-street, D'Olierstreet, and Westmoreland-street. The premises in Fleet-street are fast approaching completion, and the work of laying the mains under the streets will be commenced immediately. The company will generate electrical energy for 10,000 incandescent lamps for private residences, and for 80 arc lamps for public street lighting. The arc lamps are to be 1,000 c.p. The current will be conveyed in underground wires, enclosed in cast-iron pipes. It is intended to place in each street three sets of pipes, and each pipe will enclose two or more cables. The length of piping ordered for this purposes is six miles, and the length of cable will be about 15 miles. The electrical energy will be transmitted through the wires at a pressure of 2,000 volts. Transformers will reduce the current to the domestic lighting wire to 100 volts. The servicebox which draws off the current for each domestic lighting wire will be placed opposite alternate party-walls, so that one servicebox will supply two houses.

The public and private lighting systems will be quite distinct as regards machinery and main lines of wire. The apparatus for public lighting will consist of three high-speed engines of the vertical open front type. These engines have been built by the Brush Electrical Engineering Company, Loughborough, will run about 200 revolutions to the minute, and indicate 60 h.p. The public lighting dynamos are also of the Brush type. Instead of belting they will be worked from the engine by endless cotton ropes. The dynamos are three in number, and each will be capable of lighting 55 arc lamps, in all 165, which is more than the number required for the present by the Corporation. For the private lighting Lowrie-Hall alternators are to be used. The engines which will drive these dynamos are also specially built for the purpose by Messrs. Coates and Co., of the Lagan Foundry, Belfast. They are compound machines, capable of working up to 280 h.p., making 80 revolutions per minute, with 1531b. steam pressure in the high-pressure cylinder. The sizes of the cylinders are 17in. and 34in. respectively, and they are both lagged with steel. The steam-pipes are divided into sections, which can be worked independently, so that if an accident happened to one it may be cut off and removed for repairs, and the work go on without it. The engines are fitted with Corliss valves, Messrs. Coates's patent, which admits of very sensitive governing and economical working. The power be carried from each engine to the dynamos by means of 12 The arc lamps to be used carbon lamps, which will currents from the dynar regulato many l

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