,transcriber's ,notes3 ,underscores 80 before and after a word or phrase indicate italics in the original text4 ,equal signs 80 before and after a word or phrase indicate bold in the original text4 ,small capitals have been converted to ,,solid capitals4 ,illustrations have been moved so they do not break up paragraphs4 ,typographical errors have been silently corrected4 ,the three advertisements at the beginning of the book have been moved in front of the thirteen advertisements at the back of the book4 ,,central-,,station ,,electric ,,lighting ,,with ,,notes ,,on ,,the ,,methods ,,used ,,for ,,the ,,distribution ,,of ,,electricity4 ,,by ,,killingworth ,,hedges1 ,,member ,,of ,,the ,,institution ,,of ,,civil ,,engineers1 ,,and ,,of ,,the ,,society ,,of ,,telegraph ,,engineers ,,and ,,electricians4 ,illustration ,,london3 ,e4 ,f4 ,n4 ,,spon1 #abe1 ,,strand4 ,,new ,,york3 #ab1 ,,cortlandt ,,street4 ,all rights reserved4 ,,preface4 ,the art of lighting by ,electricity practically dates from ten years ago1 and it has during that period received the constant attention of both ,electrical ,engineers and others1 who have applied the greatest scientific knowledge4 ,the result of all this energy appears to be discouraging4 ,five hundred thousand pounds have been subscribed to carry on the business1 and it is doubtful whether the companies which survive have a market value of one-tenth of that sum4 ,the experience may have been bought too dearly1 but the era of ,central-,station ,electric ,lighting1 which has now commenced1 ought to re-establish the position of ,electricity in financial circles1 and afford a safe and profitable outlet for the surplus capital of the investor who buys gas and water shares to pay four per cent4 ,the distribution of electricity from a central-station1 which was the subject of ,sir ,william ,siemen's ,presidential ,address at the ,society of ,arts in #ahhb1 is not only accomplished from the scientific point of view1 but is also a commercial success3 the power of flowing water1 or the potential energy stored up in coal1 wood1 or other fuel1 can be utilised for lighting our streets and houses at night1 and during the day may be transmitted by means of electricity in the easiest possible way1 and supplant the gas-engine for driving small machinery4 ,a paper entitled 8,central-,station ,electric ,lighting0 was contributed by the ,author to the ,institution of ,civil ,engineers1 and was published in ,part ,,ii4 of the ,minutes1 #ahhf-hg2 the subject-matter has been extended and brought up to date1 with the object of giving a description of the systems which are practically employed in ,central-,station ,lighting at home and on the ,continent4 ,details respecting the generating plant at these stations are omitted on purpose2 technical terms would also be avoided if possible2 failing this1 it is hoped that the accompanying ,glossary will explain what is unfamiliar4 ,the amendment of the ,electric ,lighting ,act of #ahhb has given a fresh stimulus to the industry1 and many new enterprises for distributing electricity from ,central-,stations are being prepared1 and it is to be hoped that the public will profit by former experience1 and will discriminate between the good and the bad schemes which will be offered to them4 ,the organizing facilities possessed by ,gas ,companies make it desirable that they should follow the example of the ,american ,companies1 and take up the business of supplying electricity4 ,the existing powers of private companies might have to be altered1 but those municipal authorities who own the gasworks could certainly distribute electricity from a central-station1 which might be installed at the present works4 ,local authorities have certain advantages over private companies owing to the purchasing clause of the ,electric ,lighting ,act1 also the power to borrow money under this and the ,local ,loans ,act of #ahge2 should there be no department to carry out the business of supplying electricity1 the generating plant could be maintained and worked by a contractor for a fixed annual sum4 ,the remarks of ,lord ,herschell that the 8electric light is more used in the ,south ,sea ,islands than in this country0 ought to be taken as not so much referring to want of enterprise on the part of capitalists and engineers1 but to the ,electrical ,facilities ,act of #ahhb1 which has been appropriately termed a very 8boa-constrictor40 ,,killingworth ,,hedges4 #be1 ,,queen ,,anne',s ,,gate1 ,,westminster1 ,s4,w4 ,september1 #ahhh4 ,,index ,,of ,,terms4 ,,amp,,re-,,hour4--,a current of one ampre strength for one hour4 ,,current1 ,,continuous4--,the flow of electricity in one direction4 ,,current1 ,,alternating4--,the intermittent flow in two directions4 ,,conductor4--,the wire through which the current passes4 ,,circuit1 ,,primary4--,with transformers1 the conductor or leads attached to the dynamo4 ,,circuit1 ,,secondary4--,with transformers1 the conductor from the transformer to the lamps4 ,c4 ,p4--,abbreviation of ,candle-power4 ,e4 ,m4 ,f4--,abbreviation of ,electro-motive force4 ,,life ,,of ,,incandescent ,,lamps4--,the duration of the filament which produces the light4 ,,potential4--,difference of ,e4 ,m4 ,f41 or ,high and ,low-,tension4 ,see also ,glossary1 or ,explanation of ,terms1 page #ajg4 ,,an ,,electrical ,,central-,,station4 ,as the term 8central-station0 associates itself with some pretentious building1 such as a railway terminus1 it may be advisable to remark that the similarity is only in the words1 and that central-station is an abbreviation of central generating station1 or building designed to contain the plant for the public supply of electricity4 ,in the early days of electric lighting the transmission of electricity to a distance was considered an impossibility2 we find the late ,sir ,william ,siemens1 in his ,presidential ,address at the ,society of ,arts on the occasion of the opening of the session in #ahhb1 stating 8that a quarter of a mile in every direction from the lighting station was the area which would be as much as could be economically worked20 and1 in order to tap the most paying district1 it was proposed to establish a station in the most central spot4 ,sir ,william ,siemens suggested the utilisation of the public squares1 which could be excavated to a depth of twenty-five feet1 and then arched over to the existing ground level1 and in this covered space the engines1 boilers1 and dynamos were to be fixed2 the only erection above the surface was the chimney1 which was to be of ornamental design and combined with the ventilating arrangements of the subterranean chamber4 ,the great inventor1 who so ably filled the presidential chair at the meeting where these words were spoken1 would be astonished to find that in ,london one electric lighting company has already erected seventy miles of overhead wire1 and that customers are supplied miles away from the so-called central-station4 ,the changed position of electricity is due to the introduction of the transformer by ,goulard1 who showed1 at the ,turin ,exhibition of #ahhd1 that a high-tension current could be transformed into a low-tension working current of safe potential1 fifty miles away from the generator1 in a successful and economical manner1 and that the generating station might1 therefore1 be located outside the area to be lighted4 ,in large cities this is a great advantage1 the value of land often precluding the erection of a big station in the working area2 for this reason small stations are often arranged in basements1 under a large building1 which are1 as a rule1 specially designed4 ,this plan is somewhat similar to that adopted in the ,united ,states1 where it is not unusual to find a successful installation in a basement and sub-basement1 the general arrangement being of similar character to the engine-room of a steamship4 ,a station is being erected in ,philadelphia on a ground space of #gb feet #ajj feet1 which is to supply #fj1jjj lights2 the building is six-storied1 the dynamos are on the first floor1 the boilers on third1 the coal stores on fourth1 and the offices on the fifth4 ,the term 8block station0 is also used in the ,united ,states and in ,germany1 and is applied to an installation which lights a group of buildings or block without crossing any streets1 and consequently without having any wayleave or permission from local authorities4 ,,central-,,station ,,construction4 ,an ,american electrical engineer graphically sums up this question in the following manner3--8,there are two ways of starting a central-station for electric lighting--the investment or the speculative plan1 or the fair means or the foul4 ,the first has its legitimate end1 but the latter is the border ruffian or money-or-your-life policy1 which enters a territory already sufficiently covered1 not for fair competition1 but to make money by being bought out40 ,happily1 here1 we have at present only to deal with the first plan1 and the question naturally arises1 8,is electric lighting a paying investment80 ,it certainly will not be if the object in view is only to compete with gas in a limited district where perhaps it is being sold at #bs4 #f;d4 per #ajjj feet1 for1 as long as there is a ready market for the coke and other by-products1 gas will remain in possession of the field4 ,the heat from gas1 which is found so undesirable by the wealthier classes1 is advantageous to those who perhaps cannot afford a fire2 in fact1 gas has been truly called the 8poor man's friend10 and1 until electricity can be supplied at a nominal price1 it will be useless to expect any revenue from the poorer districts of large cities4 ,quite an opposite result may be looked for when the electric mains are laid at the doors of the wealthy householder1 or through the business neighbourhoods4 ,shop-owners especially are found to immediately take up electric light1 from the fact that no fumes are given off to destroy goods or tarnish silver or gilding1 and because it can be so easily applied in a shop window so as to efficiently light the contents without producing shadows4 ,the great object to be aimed at in selecting a district to be served from a central-station is a 8constant demand10 and for this reason it is advantageous to include a business neighbourhood with shops1 public-houses1 and restaurants1 which require the light for a definite period every day1 and probably will each take more than double the amount of an ordinary dwelling-house2 in fashionable neighbourhoods especially1 it is not unusual to find a large number of houses vacated at the close of the season1 the interest on that portion of the electric system which is unemployed will have to be set against the profits of other periods of the year4 ,the number of gas lights which are actually used at one time in a house is found to average only two-thirds of the total number fixed1 and with electric light this number is reduced to one-half2 economy is at once the rule with electric light1 partly because of the novelty of the illuminant1 and also on account of the facility of lighting and extinguishing by simply turning a tap or switch4 ,the number of hours artificial light is wanted in a residential district may be taken at about #ajjj hours per annum1 that is to say1 the light is required for about four hours a day in winter and two hours in summer2 this amount is very much exceeded in clubs1 shops1 and even in large houses1 but #ajjj hours is a safe figure1 and1 if the supply is taken by meter1 an annual payment equivalent to #ajjj hours' supply should be a fixed amount to be paid for1 whether used or not4 ,mr4 ,crompton estimates that a ,londoner1 who is a tenant or owner of a house having three reception rooms1 ten bedrooms1 and usual offices1 spends about #be a year for his lighting1 which is made up as follows3--gas bill1 #ae2 lamp1 oil1 candles1 matches1 about #aj4 ,there would be about fifty burners fixed2 and1 supposing fifty electric lights to be substituted1 he could be supplied with electricity for #be a year1 at a fair profit to the supply company if they charged #h;d4 per ,board of ,trade ,unit1 as practice has shown that the total number of lamp-hours with fifty electric lamps is not more than sixty-two1 so that two ,units1#a or #as4 #d;d4 per day1 would be sufficient for the lights he would require4 #a ,unit2 see page #g4 ,the diagram1 ,fig4 #a1 taken from a ,london residential district1 shows how the number of lamps on at one time vary2 the district is supposed to be wired for #aj1jjj lamps1 and the plant as equal to the supply of #fjj kilowatts1 or #fjj1jjj watts2 the number of lamps is small until about #c o'clock1 when it gets dusk on a winter afternoon2 it then increases steadily until about #f4cj o'clock1 when the curve goes up with a rush2 about this time a great number of people are preparing for dinner1 and probably the lights are on both in the dining-room and bedrooms4 ,the curve falls1 and at about #h it begins to sink gradually until #aj o'clock2 a great many people appear to go to bed about this time1 but a few sit up to #a o'clock2 until #f the next morning hardly any supply is taken1 when the servants get up and prepare the rooms for the day4 ,the diagram1 ,fig4 #b1 is taken from the ,edison ,company's central-station at ,cincinnati1 and agrees fairly with the ,london demand for light4 ,another interesting fact has been ascertained from the observations taken at the ,mauer ,strasse station in ,berlin1 namely1 that the output varies with the temperature1 it goes up or down with the thermometer4 ,the reason is easily explained2 gas is laid on side by side with the incandescent lamps1 and the burners are first lighted when it is cold to warm the apartments2 in warm weather the electric light alone is used4 ,from these and other diagrams the very important fact has been obtained1 that the average daily output of a station throughout the year is less than one-third of the total capacity of the generating machinery1 so that1 although the station from which the diagram in ,fig4 #a was taken could maintain #aj1jjj #af candle-power lamps simultaneously alight1 the average daily output of electricity would only equal #cejj constantly lighted2 and1 as the first cost of the station is dependent on the size of the plant1 the saleable output is the important factor which governs the profits4 ,illustration3 ,,fig4 #a4 ,illustration3 ,,fig4 #b4 ,,charges ,,for ,,electricity4 ,the well-known expression 8per #ajjj ,cubic ,feet0 is not applicable to electric light1 and1 instead1 the ,board of ,trade ,unit is employed4 ,by this term ,unit is meant the quantity of energy contained in a current of #ajjj ,ampres flowing under an ,electro-motive ,force of ,one ,volt during ,one ,hour4 ,in the early days of electric lighting the term ,volt-ampre was used1 and has for convenience sake been shortened to ,watt2 that is1 the ,volt or ,unit of ,electro-motive ,force 7or pressure7 is multiplied by the ,ampre or ,unit of current4 ,the ,board of ,trade ,unit is1 therefore1 a ,thousand ,volt-ampres or ,watts per hour4 ,for example3 #af candle-power ,swan lamps are assumed to take #fj ,watts1 which1 if the electrical pressure is #ajj ,volts1 would mean a consumption of #jf ,ampre2 and1 as an ,electrical ,horse-power equals #gdf ,watts1 #abd lamps should theoretically be obtained per ,horse-power1 which is1 however1 reduced in actual practice to #aj at the most1 often less4 ,the charge per ,unit supplied by meter varies in ,england from #as4 to #g;d4 ,price for electric ,equivalent price for gas of equal light4 light4 s4 d4 s4 d4 #a #j per ,board #f #aj per #ajjj cubic feet4 #j #i of #e #a 0 0 #j #g ,trade #d #b 0 0 #j #f ,unit4 #c #e 0 0 ,comparison of ,cost of ,gas and ,electricity4 ,these prices1 of course1 include the manufacturer's profit as well as the loss in transmission through the mains and expenses of connecting up to the consumer4 ,the actual manufacturing cost of a station maintaining #aj1jjj lights should not be more than #c;d4 per ,unit1 or equivalent to gas at #as4 #h;d4 per #ajjj cubic feet4#b #b ,see ,table ,,iv41 page #hg4 ,as petroleum lamps are used for the street lighting of many foreign and colonial towns1 the question arises1 8,will it pay to substitute the electric light80 ,comparing the light given by a kerosene or petroleum lamp with that from the incandescent electric lamp1 the cost is greatly in favour of oil2 and1 in fact1 where the price of kerosene is under #as4 per gallon1 electricity cannot compete if labour is cheap4 ,on the other hand1 the trimming1 lighting1 and keeping in order of a number of lamps scattered over a large area greatly augments the working cost1 to which must be added the breakages of chimneys1 expense of wicks1 also the danger of fire4 ,it is the safety of electricity which has caused it to supplant oil both for public and private lighting in ,american cities2 even where the price of kerosene is not more than #f;d4 per gallon there is a demand for the electric light1 which is by far the dearer illuminant1 after making a liberal allowance for labour in cleaning1 filling1 and lighting the oil lamp1 also for depreciation of the burners4 ,arc and ,incandescent or ,glow ,lighting4 ,illustration3 ,,fig4 #c4 ,electric lighting can be obtained by means of arc or incandescent lamps4 ,the arc light is now well understood to be caused by the extremely high temperature of the end of one or both the carbon electrodes4 ,the voltaic arc1 ,fig4 #c1 is formed by the minute particles of carbon in a high state of combustion which the current appears to break off and carry from one electrode to the other1 the light1 however1 being mainly due to the incandescence of the crater shown in ,fig4 #c on the upper carbon4 ,in the incandescent or glow lamp light is produced by the passage of a current of electricity through a continuous fine thread or filament of carbon which becomes white-hot1 the destruction of the filament being prevented through its enclosure in a glass bulb from which the air is exhausted4 ,figs4 #d and #e4 ,the first method is suitable for the lighting of streets where a high-class illumination is required2 also will be wanted for the external lighting of shops1 public-houses1 and places of amusement1 so that arrangements must be made for arc lighting4 ,the usual plan is to charge at the same rate per ,unit by meter as the incandescent lamps1 but to make an additional charge of #es4 to #gs4 #f;d4 per lamp per quarter for rent1 and a further charge of #cs4 per week for cleaning and trimming4 ,the principal types are the ,edison and the ,swan1 ,fig4 #d and ,fig4 #e4 ,incandescent lamps can be obtained to order from #a candle-power upwards1 but the #af candle-power 7nominal #bj7 or the #h candle-power 7nominal #aj7 lamps are almost invariably employed4 ,the latter give the best effect1 and can be worked to #aj candle-power without much risk1 they take about #cj watts as against #fj watts for the #af candles2 and are not uneconomical1 for nearly double the number can be worked with the same energy4 ,a new type of glow lamp1 called the 8,sunbeam10 has been recently introduced1 which contains a thick filament1 and gives a light of from #bjj to #aejj candle-power1 and can be employed instead of an arc lamp with the same economy as the ordinary #af candle-power type4 ,illustration3 ,,fig4 #d4 ,,fig4 #e4 ,life of ,incandescent ,lamps4 ,in estimating the annual cost of lighting1 the renewals of lamps must be taken into account2 and although some lamps have worked #cjjj or even #djjj hours1 a life of #ajjj working hours is the highest average it is safe to assume in practical work under even the best conditions1 that is1 using secondary batteries and never over running4 ,the average life of #acj lamps on ,h4,m4,s4 troopship ,malabar was #cgii hours each1 the shortest life being #fch hours for #ah yard-arm lamps of #cb candle-power4 ,if the current is allowed to fluctuate1 the average life would be very much less2 it is an unsettled question whether long-lived lamps are really economical1 by reason of the blackening of the globes1 which takes place after the lamp has been worked some time1 and is probably due to small particles of carbon thrown off from the filament being deposited on the glass4 ,it has been suggested that attrition of the filament is going on all the time the lamp is at work1 and that the heated atoms striking against the filament may account for the blackening1 in that the mean free path of the atoms would be greater in a perfect vacuum than in the air1 consequently they would abrade the filament with considerable force4 ,if lamps were sold at #as4 each instead of #cs4 #f;d41 which is now the price for not less than a thousand1 it would be more economical to change them at the first signs of blackening1 even if the life did not exceed #ejj hours4 ,the diagram1 ,fig4 #f1 has been so arranged that the amount of light required in a given district can be ascertained for any period of the day or night2 it has been calculated from the observations taken daily at one of the ,berlin central-stations by the engineer to the company4 ,six hundred and forty watts are assumed1 for the purposes of the diagram1 to be the equivalent of a horse-power1 instead of #gcf1 as the ,german electrical horse-power is #gcf watts instead of #gdf watts4 ,illustration3 ,,fig4 #f4 ,the table1 ,fig4 #f1 has two vertical scales1 ,a and ,b1 each giving the kilowatts#c and corresponding horse-power4 ,a is drawn to a scale ten times greater than ,b1 with the object of noting the smaller amount of lights required for street illumination4 ,the horizontal line is divided into hours1 and represents a day's lighting in the middle of ,december and the end of ,july1 so as to show the maximum and minimum amount of current that will be required4 ,in the lighting of a town there are two classes of illumination1 the amount taken by the public1 which is uncertain1 and that employed for street lighting1 which is a known quantity4 #c #ajjj watts4 ,the curves1 ,,ii and ,,ii ,a1 represent the private lighting of houses1 hotels1 theatres1 and shops of different kinds in ,december and in ,july1 the curve1 ,,ii ,a1 being in dotted lines clearly shows what a vast difference there is in the amount of light1 and consequently the amount of energy required in the generating station1 as compared with curve ,,ii1 which is taken when the days are longest4 ,the rectangles1 ,i and ,i ,a1 show the street illumination1 and are drawn to suit scale ,a2 half an hour after sunset all the lamps are turned on1 and the work reaches its maximum suddenly1 and continues the same until #ab o'clock1 when1 according to the municipal decrees1 it either falls one or two gradations until half an hour before sunrise1 when all the lamps are extinguished4 ,the calculations are based on the assumption of #fdj watts to the horse-power1 instead of #gcf1 which is the theoretical efficiency of a ,german horse-power4 ,if a number of diagrams are taken on this method for different periods of the year1 the constant work can be ascertained4 ,this knowledge is most valuable when calculating the most economical area for the mains1 which is then easily accomplished by means of ,forbes' tables1 which are based on ,sir ,william ,thomson's well-known rule4 ,the lines1 #b and #b ,a show the constant work at the same two periods of the year from which the diagrams are taken4 ,the constant work at the end of ,december will be found to amount to #bj per cent4 of the total work1 and that at the middle of ,june to #ae per cent4 ,by summing up the average work for all the days in the year we obtain the cost per annum1 and adding to this the expense of management1 interest1 c41 and knowing the local conditions1 we can fix what proportion of the day's work is admissible as loss4 ,with the ,edison system at ,berlin1 #e per cent4 is taken as average loss2 thus1 at the end of ,december1 it amounts1 with the maximum number of lights1 to #ahh per cent41 and with the minimum to #aa per cent42 in the middle of ,july the maximum is #aeh per cent41 and the minimum #je per cent4 ,the dynamos must1 of course1 be of sufficient power to be able to overcome this loss1 which only shows itself periodically2 therefore the generating plant may be constructed to give1 nominally1 #bj to #cj per cent4 less than the maximum work1 and be capable of being pushed to the full amount for a short time only4 ,,the ,,position ,,of ,,central-,,station ,,lighting4 ,uncontrolled financial speculation1 aided by the stringent clauses of the ,electric ,lighting ,act of #ahhb1 have been a great deterrent to the extension of old or the introduction of new schemes for the supply of electricity to the public in the same manner as gas4 ,the ,president of the ,board of ,trade1 replying to a question in the ,house of ,commons1 said that1 8since the passing of the ,electric ,lighting ,act of #ahhb1 fifty-nine provisional orders and five licences had been granted to companies1 and fifteen provisional orders and two licences to local authorities4 ,he was not aware that1 in any single case where these powers had been obtained1 they had been exercised40 ,up to the present time no company supplying electricity has been under the necessity of applying for compulsory powers1 and has either obtained permission from the local authorities to take up the streets1 or has carried the electric mains over the houses1 and1 regardless of the question of overhead wires1 has depended on wayleaves granted by the too-confiding householder1 who has no idea that his roof is supporting a cable weighing #a tons to the mile4 ,an amendment of the ,act of #ahhb has passed both ,houses without hindrance1 and has received the ,royal assent4 ,it provides that in the case of ,provisional ,orders the period after which the undertaking may be bought up by the ,local ,authority shall be extended from twenty-one to forty-two years1 and that portion of the previous ,act which referred to the compulsory purchase of the undertaking by a local authority at the end of the term has been altered1 and more favourable terms given to the electric companies4 ,on the ,continent1 and in the ,united ,states1 where each city may be said to legislate for itself in matters relating to the general welfare of its citizens1 the electric lighting industry is in a very different position1 and central-stations are either established or about to be started in every important town4 ,there were1 in #ahhg1 #aba ,edison central-stations alone1 supplying over #cbc1jjj incandescent lamps1 and paying dividends from #f to #ad per cent4 ,the ,westinghouse ,company1 who use a transformer system which is a modification of the ,goulard and ,gibbs1 have a hundred stations1 maintaining #aia1jjj lamps1 although the first ,westinghouse plant was put down only three years ago4 ,the progress in the ,united ,states is so rapid1 and there are so many successful applications of central-station lighting1 that the subject becomes too large to be even summarised1 so that it is proposed to treat in the following pages with some of the principal installations on the ,continent and at home4 ,travellers abroad are accustomed to find electric lighting installed in the most out-of-the-way places1 especially in ,switzerland1 where water power is abundant and is utilised to generate electricity1 so that in small hamlets arc lighting is often employed1 and the visitors to the local hotel will find it lit throughout by electricity4 ,electric light stations in ,england are1 with one exception1 small in comparison with those on the ,continent4 ,the most important is that at the ,grosvenor ,gallery1 ,london1 which has increased from small beginnings until it now supplies #bj1jjj glow lamps on sixteen circuits1 the total length of which is seventy miles4 ,the next largest1 which have been in practical work for some time1 are the ,brighton and ,eastbourne stations1 from which small installations of glow and arc lights are maintained in various districts of the two towns4 ,that the question of cost or trouble1 and the annoyance of machinery when erected in a dwelling-house1 do not altogether prevent the adoption of a superior light1 is clearly proved by the increasing number of householders1 who1 after waiting in vain for electricity to be brought to their doors1 have set up the plant necessary to produce it themselves1 and find no practical difficulty in doing so4 ,there are also many important public works where electric light has been exclusively adopted4 ,for instance1 at the ,tilbury ,docks there are #acej glow and #hj arc lamps1 distributed over an area of #cjj acres1 and including the lighting of an hotel1 dock sheds1 warehouse1 signal-boxes1 and offices4 ,the ,london1 ,chatham1 and ,dover station at ,victoria has also been electrically lighted for the past three years1 the current being obtained from a central-station1 which was erected for the purpose of supplying electricity to the ,victoria district1 and for which a provisional order was obtained4 ,this1 however1 has since been abandoned1 although #af1jjj had been expended on plant and buildings by the promoters1 who preferred to postpone the scheme rather than to submit to the onerous #bgth clause of the ,electric ,lighting ,act4 ,another still larger installation has been put down to supply electricity to the ,paddington station and district of the ,great ,western ,railway1 as far as ,westbourne ,park4 ,it embraces an area of sixty-seven acres1 and is lighted by #daae glow and #ih arc lamps4 ,the system adopted is that designed by ,mr4 ,j4 ,e4 ,gordon1 and has now been successfully worked for some time2 but the many accessories which are introduced1 such as telephones1 telegraphs1 and indicators1 make it complicated in comparison with gas1 or even with the ordinary electric light systems4 ,the current is generated by two dynamos1 each weighing #de tons1 and having revolving magnet wheels #i feet #h inches in diameter1 #bb tons in weight1 a third machine being kept in reserve4 ,these dynamos are separately excited1 and produce alternating currents4 ,the electricity is led to a large switch-board for distribution throughout the district by means of five sub-stations2 and from this board there branches a double system of mains1 which run everywhere side by side1 one-half the mains being connected to the first machine and one-half to the second1 so forming an excellent arrangement for the prevention of total extinction of the light4 ,the mains running to the sub-stations are on the divided system1 which is introduced for the purpose of saving copper1 as in a solid cable the loss of pressure is greatest when the full number of lamps is on1 and decreases as the lamps are extinguished4 ,with the divided main system it is intended to follow out ,sir ,william ,thomson's formula1 which equates the value of the loss of head1 and the interest on the saving on the copper4 ,if for a certain main this formula shows that a fall of #bj per cent4 is the most economical condition for working1 then1 since by the divided main the pressure can be kept within a variation of #b per cent4 at the distant end1 it follows that a considerable saving can be effected over an ordinary solid main4 ,special arrangements are adopted at ,paddington to keep the pressure constant1 a fall of potential being allowed for2 thus at the engine-house the pressure is #aej volts1 in the passenger station it is #abj volts1 and at ,westbourne ,park it is #ajj volts4 ,the arc lamps are fed by the same mains1 and are arranged two in series4 ,a small installation at ,kensington ,court1 erected two years ago1 for the purpose of supplying the houses in the immediate neighbourhood1 has rapidly developed1 and underground mains have been led in many directions from the station1 and a constant service of electricity is provided for by means of secondary batteries4 ,as this is the first practical exposition of the secondary batteries' system of distribution1 it is proposed to describe the installation under that head4 ,central-stations are also at work in ,liverpool1 ,leamington1 ,taunton1 ,exeter1 and there are also five large installations nearly completed in ,london1 besides the ,kensington ,court station1 all of which will probably be in full swing before the end of the year4 ,,electric ,,lighting from ,,central-,,stations is now practically carried out on five different methods4 ,i4 ,,by ,,secondary ,,generators ,,or ,,transformers1 ,,with ,,alternating ,,current4 ,,ii4 ,,the ,,edison ,,or ,,parallel ,,system1 ,,with ,,continuous ,,current4 ,,iii4 ,,the ,,series ,,or ,,bernstein ,,system4 ,,iv4 ,,multiple ,,series4 ,v4 ,,distribution ,,with ,,secondary ,,batteries ,,or ,,accumulators4 ,,class ,i4 ,,supply ,,by ,,secondary ,,generators ,,or ,,transformers4 ,the problem of electric lighting from central-stations is comparatively easy if an area can be obtained immediately surrounding1 and within a short distance of1 the station1 with a right of way for laying down the electric mains direct4 ,this happy state of affairs has not yet been attained1 consequently the generating station has more often to be in an out-of-the-way corner of the district to be lighted1 and it would be financially impossible to use low-tension currents with correspondingly large mains4 ,the difficulty has been overcome in several ways by the use of high-tension currents in the mains1 and has led to the adoption of secondary generators or transformers of electricity1 which by induction supply a current of low potential in the house-service4 ,the first to make this plan a practical success was ,mr4 ,goulard1 to whom the honour of the introduction is due1 although his claims as the first inventor have been recently upset by the decision of the ,courts4 ,the relative economy of the supply of electricity by the use of a transformer is clearly shown by the following diagram1 ,fig4 #g4 ,a1 ,b1 and ,c give proportionately the area of cross section of the total mass of copper necessary to supply #ejjj #af candle-power glow lamps situated at a mean distance of #djjj feet from the dynamo4 ,a refers to the ,edison 8three-wire0 system1 working at a potential or electrical pressure of #bjj volts with a fall of potential or loss of energy in the distributing feeders of #aj per cent41 average distance from dynamo #djjj feet--the usual conditions on which this system is worked4 ,b shows the size of conductor required for the same work in an installation based on the transformer system1 potential #ajjj volts1 allowing #be per cent4 loss in the supply mains--only one-fourth as much as in the direct ,edison system at the same average distance from dynamo4 ,if this loss were increased to #aj per cent41 and made equal to that in the direct system1 viz4 #aj per cent41 the size of the conductor would be that shown at ,c4 ,illustration3 ,,fig4 #g4 ,illustration3 ,,fig4 #h4 ,the graphic diagram1 ,fig4 #h1 demonstrates what the relative cost would be with each of the three conditions just named4 ,mr4 ,goulard's first practical application of the secondary generator in this country was the lighting of the ,underground ,railway ,stations1 in #ahhc1 from ,edgware ,road to ,high ,street1 the generating dynamo being fixed at the former place4 ,these experiments1 which were made by ,mr4 ,kenneth ,mackenzie1 attracted considerable attention at the time1 but it was not until the report of the jurors to the ,turin ,international ,exhibition in #ahhe was published that companies were formed to instal the ,goulard system for lighting an extensive district4 ,illustration3 ,,fig4 #i4 ,the principle underlying all transformers is that of the induction coil invented by ,ruhmkorff in #ahdb1 but described by ,faraday in his 8,experimental ,researches10 published in #ahca-b4 ,fig4 #i is a diagram of the ordinary induction coil2 on a central core is wound a short length of thick wire called the primary1 and again over this is wound a greater length of fine insulated copper wire which forms the secondary coil4 ,on sending a low-pressure current from the generator round the thick wire1 a much smaller high-tension current is induced in the secondary4 ,a contact breaker is employed to make and break the current1 or1 as in the early instruments1 a commutator may be used to produce the alternations4 ,when used as a transformer the action is reversed1 that is1 a high-tension current is passed through the primary coil1 which is composed of a wire of small sectional area1 the high-pressure main connected to the dynamo also being small as compared with the distributing cable leading from the transformer1 which1 acting as a step-down induction coil1 converts the electricity into a safe working pressure4 ,illustration3 ,,fig4 #i;,a4 ,fig4 #i ,a shows the arrangement of the two separate and complete circuits4 ,d is the dynamo1 ,p the primary coil1 ,s the secondary1 and ,l the lamps arranged in parallel4 ,it is hardly necessary to go into the technical details of the various improvements which have led up to the modern type of transformers2 they are summarised by ,mr4 ,kapp into two classes3-- ,i4 ,core transformers1 one core and two sets of coils4 ,,ii4 ,shell transformers1 two cores and one set of coils4 ,no4 ,i4 are those in which the copper coils are spread over the surface of the iron core enveloping the latter more or less completely2 and ,no4 ,,ii4 in which the core is spread over the surface of the copper coils forming a shell over the winding4 ,illustration3 ,,fig4 #aj4 ,the original ,goulard and ,gibbs secondary generator was of the core transformer type1 it had an open magnetic circuit and cores which could more or less be inserted into the coils so as to regulate the electro-motive force of the secondary circuit4 ,the transformers were constructed with a number of copper disks or washers2 these were placed alternately primary and secondary in a vertical frame1 through the centre of which an iron core was fixed1 consisting of a bundle of straight iron wires4 ,the core was movable in the coil in the manner of the well-known induction coils1 and thereby the electro-motive force of the secondary current could be adjusted4 ,in their latest design the coils are circular in plan and rectangular in section and are surrounded by groups of ,u-shaped soft iron stampings slipped over from both sides and held together by two circular cast-iron plates with a central bolt4 ,the magnetic lines of force pass through the core1 in at one end and out at the other1 and are then more or less disseminated through space2 it will thus be seen that the path of the lines lies partly in iron and partly in air1 and1 since air has about seven hundred times more magnetic resistance than iron1 it is evident that the number of lines created with a given current must be considerably smaller than would be the case if the path of the lines contained iron only4 ,this constitutes the improvement in the ,zippernowsky-,deri-,blathy system of transformer1 which has coils similar to the ,goulard1 but with the iron of the core applied in the form of a ring-shaped shell1 surrounding both coils completely4 ,this arrangement can best be described by comparing it to a ,gramme armature1 in which the copper and the iron have changed places4 ,imagine what is usually the core in an armature replaced by the primary and secondary coils1 and1 instead of the winding of insulated copper wire1 wind iron wire around the coils1 and one of these transformers is the result4 ,in consequence of the lower magnetic resistance of the ,class ,,ii4 transformer1 as compared to that of ,class ,i41 the electrical output obtainable with equal weights of copper and iron appears to be considerably greater in the former apparatus4 ,professor ,feraris1 of ,turin1 has published some of the results of comparative experiments made with ,classes ,i4 and ,,ii4 and finds that the coefficient of induction is #cf times as great with the latter as with the former4 ,there are many varieties of transformers in the market which closely resemble each other2 one of the most practical is that designed by ,kapp and ,snell1 of which ,fig4 #aj is an illustration4 ,u-shaped stampings form the shell and the cores are laid in the double trough4 ,the cover of these troughs is formed from the metal removed from the interior of the stampings1 and the whole is held together in a cast-iron frame so arranged as to allow air to circulate through the core and round the coils4 ,the price of these transformers is about #d per indicated horse-power1 and the efficiency under the best conditions1 namely1 with full load1 is1 according to ,professor ,ayrton1 as high as #if per cent41 and when it is doing one quarter of the full work #hi per cent4 ,,application ,,of ,,transformers4 ,the installation at the ,grosvenor ,gallery1 ,london1 may be taken to illustrate ,class ,i4 or the practical working of distribution by means of transformers4 ,fig4 #aa represents the arrangement of primary and secondary circuits4 ,an alternating current is sent through the main ,l ,l1 which is a closed circuit1 and a small portion is drawn off wherever there is a secondary generator or transformer ,t2 these instruments are placed in parallel between the conductors in the same manner as a glow lamp2 neither main can be called positive or negative1 as the current flows backwards and forwards many times in a second4 ,the house wires ,m ,m are joined to the secondary circuits1 and are quite distinct from the main1 which they do not even touch1 although sufficiently near to receive an induced current alternating the same as the primary1 but of a much lower electro-motive force4 ,illustration3 ,,fig4 #aa4 ,d1 alternating current dynamo2 ,e1 continuous current dynamo for exciting2 ,l ,l1 main primary conductors2 ,m ,m1 secondary conductors2 ,t ,t1 transformers2 ,s ,s ,s ,s ,s ,s1 lamps in parallel4 ,the ,goulard transformers were used at first1 but have been superseded by others designed by ,mr4 ,ferranti2 they are of the ,no4 #b kind1 or shell type1 and have a core of hoop-iron1 on which the two coils are wound2 the hoop-iron is then bent over1 and the ends joined so as to enclose the coils4 ,the machinery is fixed in a basement excavated under the ,grosvenor ,gallery2 the foundations are of massive concrete1 in which stone supports for the engines and dynamos are embedded2 the concrete does not touch the walls of the building1 but a space of about #a foot is left1 which is filled in with clay2 and by this simple plan all vibration of the machinery is isolated from the building4 ,the power is obtained from two horizontal high-pressure engines1 each of #fjj indicated horse-power1 in addition to the original two horizontal high-pressure non-condensing engines1 each of #ce nominal horse-power1 running at a speed of #ee revolutions per minute1 which is maintained constant by means of a governor directly attached to the expansion slide-valve4 ,the four engines drive on to a countershaft1 which is cut up into lengths2 each section is coupled to a dynamo and exciter by means of a conical friction-disk clutch2 this permits of either length being started or stopped without interfering with the other4 ,the speed of each engine is checked by means of a liquid speed-indicator1 designed by the author4 ,two ,ferranti alternating current dynamos1 each capable of maintaining ten thousand lamps1 are driven direct1 one dynamo by each length of shafting3 they are excited by two continuous current machines1 the circuits from which are joined to a regulating apparatus1 which by altering resistance keeps the electro-motive force of the large machines proportional to the number of lamps which are to be maintained4 ,at present hand regulation is employed1 but it is proposed to use automatic regulation1 which will increase the life of the lamps1 as they are severely tried by the variation of the current1 which is more noticeable than in continuous current installations4 ,the current from the machines is at a potential of #bdjj volts1 and that from the transformers is #ajj volts4 ,the primary wire which carries this high electro-motive force does not enter the houses1 as the transformers are1 as a rule1 fixed in the cellars1 and from them the house branch is led in the form of a cable of fine wires1 having a total diameter of #g_/af inch2 the lamps1 which are placed in parallel across this cable1 are attached to single ,no4 #ah or ,no4 #bj ,b4 ,w4 ,g4 wires in the usual manner4 ,when first established1 the transformers presented an element of danger1 in that they1 in common with all induction coils1 were also condensers1 and therefore a dangerous shock might be given to any one touching some unguarded portion of the lighting system4 ,this has been prevented by the simple plan of connecting one of the terminals of every secondary circuit to earth1 a method which1 however1 is not to be recommended1 as it throws an additional strain on the insulation of the primary circuit2 in fact1 by earthing the secondary the insulation is practically reduced to one-half4 ,a safety device should be inserted1 which would come into operation on any leakage from primary to secondary1 and immediately cut out the transformer4 ,the primary-current conductor is led overhead1 and still remains an objectionable feature of the system1 although the original trouble with the neighbouring telephones and telegraphs has been overcome4 ,the primary circuit is a small carefully insulated cable of high conductivity copper wire1 nineteen strands of ,no4 #ae ,b4 ,w4 ,g4 ,it weighs about #a ton per mile1 and is suspended1 where it crosses the streets1 on a steel bearer whose tensile strength is #a ton4 ,it is so arranged according to the droop of the cable that the strain of the bearer never exceeds #bbe lbs41 which means that the factor of safety is nearly #ab to #a4 ,double cut-outs or safety fuses1 in many instances of the author's design1 are placed on each pole of the primary1 at the point where it enters the house1 so that1 in the case of an excess current1 the mica-foils would fuse1 and all connection between that house and the supply main would cease4 ,much credit is due to ,m4 ,goulard1 who1 in spite of great opposition to the use of his transformer system1 initiated the ,grosvenor ,gallery installation three years ago4 ,it has developed into not only the largest and most important central-station in ,europe1 but1 as regards the transformer system1 it supplies more lights than any in the ,united ,states4 ,the original company has been taken over by the ,london ,electric ,supply ,corporation1 who are putting down plant capable of maintaining #cj1jjj lights1 and are erecting another station at ,deptford for #bjj1jjj lights1 which will be distributed by means of district transformers from mains1 which it is proposed to run from ,deptford through the ,thames ,tunnel and the ,underground ,railways4 ,the electric current is supplied by meter at the price of #g;d4 per ,board of ,trade ,unit1 a price for light equal to gas at about #ds4 #b;d4 per #ajjj cubic feet4 ,the ,eastbourne station is also on the transformer system4 ,an alternating current dynamo1 by ,ellwell ,parker1 maintains a pressure in the primary circuit of #bjjj volts1 which is reduced by means of a ,lowrie ,hall transformer to a working pressure of #ajj volts4 ,there is a special arrangement for maintaining a constant electro-motive force in the mains1 independent of the number of lights in use4 ,the mains are carried underground1 and have so far given no trouble as regards the insulation of the high-tension current which passes through them4 ,the ,eastbourne company commenced by lighting the parade only with arc lamps1 but now supply the incandescent light to all parts of the town1 and enjoy the unique position of having obtained power from the corporation to run the mains in the streets prior to the passing of the ,act of #ahhb4 ,another small station has been successfully worked for the last six years at ,brighton2 the group system was originally adopted1 the lamps1 both arc and incandescent1 being placed in series or multiple series2 the high-tension current is led through overhead wires in a very similar manner to the installation at ,temesvar1 ,hungary1 which is described at page #eh1 as an example of multiple series lighting4 ,the extensions at ,brighton are to be carried out on the transformer plan1 which will necessitate the running of separate circuits1 the intention of the company1 however1 being to gradually convert its whole system of supply to the transformer system4 ,the ,brighton ,company has regularly paid dividends to its shareholders since its formation4 99 99 99 99 99 ,on the ,continent the ,goulard transformer is largely employed4 ,an important installation at ,tours of #cejj lamps has been for some time successfully working4 ,another at ,tivoli has some additional points of interest1 in that the natural power of a waterfall is applied to generate electricity4 ,two turbines constructed by ,escher ,wyss1 of ,zurich1 having an available head of #bige feet1 give #hj horse-power each1 which is employed to drive two ,siemens alternating current dynamos1 separately excited by two small continuous current machines4 ,two distinct circuits of chromo-bronze naked wire1 #cg millimetres in diameter1 are run overhead1 in the same manner as telegraph wires1 through the town for a total length of about nineteen miles4 ,the street lamps are fixed alternately on each circuit1 so that one-half can be extinguished at a late hour without interfering with the others1 or having to turn out individual lamps4 ,the number of lamps used in the streets is two hundred glow lamps of #ej candle-power2 also one hundred and twenty glow lamps of #af candle-power for the illumination of the narrower streets4 ,arc lamps are also employed1 as well as a large reflector lamp1 the rays from which are turned on the ,temples of ,vesta and ,sibilla4 ,a house-to-house system is also being established1 and the company which has put up the work proposes to utilise the falls of ,tivoli in order to transmit #bjjj horse-power for lighting purposes in ,rome4 99 99 99 99 99 ,the firm of ,ganz1 of ,budapest1 who are the manufacturers of the ,zippernowsky-,deri-,blathy system of transformers1 have a similar installation completed in order to light a portion of ,lucerne4 ,the water power of ,thorenburg #ca miles off1 works the turbines1 which drive two self-exciting alternating current dynamos of the ,ganz type1 similar to those shown at the ,vienna ,exhibition in #ahhd4 ,the primary current of #ch ampres1 at an electro-motive force of #ahjj volts1 is led by four uncovered wires1 each six millimetres in diameter1 to the first station1 which is #bd kilometres distant2 here #aejj watts are taken off1 and at #bc kilometres further #gjjj watts are utilised in two of the hotels at ,lucerne4 ,a large installation on the same system has been put down in ,rome1 and several ,continental cities are adopting this method of supplying electric light by small overhead wires4 ,an advantage claimed by the ,zippernowsky system is the method of keeping the strength of the magnetic field of the dynamos in accordance with the external demand for current4 ,the regulating apparatus employed consists of a small transformer1 the primary coil of which is traversed by the whole1 or by a proportionate part1 of the main circuit1 while the secondary coil is inserted into the exciting circuit4 ,thus1 if the main current increases1 the exciting current induced in the two armature coils of the dynamo is reinforced by the inductive action of the regulating transformer2 and the field of the dynamo is strengthened when more current is required4 ,the opposite takes place when1 through the extinction of lamps on the external circuit1 the demand for current becomes less4 ,in an experiment made with the transformers1 which supply some five hundred electric lamps for the ,teatro dal ,verone and adjoining houses at ,milan from the central electrical station three-quarters of a mile away1 the main current was often found to vary from one ampre to thirty-five ampres2 it was stated that no variation in the service pressure could be detected1 and the lamps burnt with equal brightness whatever the number in use4 ,in the experiments at the ,teatro dal ,verone each transformer worked its own independent circuit of lamps2 but1 if the conditions of the different circuits were alike1 they could be coupled up together in any manner desired1 and thus a group of transformers could become a centre of distribution4 ,,the ,,westinghouse ,,system4 ,the alternating current system of the ,westinghouse ,company has come to the front in the ,united ,states with extraordinary rapidity1 and1 although it is not three years since the first plant was erected1 at the present time over #aij1jjj incandescent lamps are operated from a number of central-stations4 ,the fundamental principles of the ,goulard system have been retained in the ,westinghouse converter2 but the manner in which these principles are applied has been greatly modified1 while most of the details have undergone a radical change at the hands of the engineers and electricians whose researches have been utilised by the ,westinghouse ,company4 ,the form of converter as now designed consists of a number of thin sheet-iron plates1 shaped like the letter ,e1 they are slipped alternately from opposite directions over the primary and secondary coils1 which are disposed side by side2 the inductive core is1 therefore1 composed of a mass of detached plates insulated from each other by paper1 and forming a discontinuous magnetic circuit4 ,in order to protect the converter from mechanical injury as well as dampness1 and also to avoid the possibility of contact with wires carrying currents of high potential1 it is enclosed in a cast-iron case or box1 made in two parts and adapted to be secured to any convenient support4 ,fig4 #ab is a transverse vertical section of such a converter box1 with the converter in position4 ,the terminals of the primary coil1 ,p1 of the converter are led into the compartment ,d1 and the terminals of the secondary coil into ,d4 ,the terminals are secured to bolts or couplings1 f f1 mounted upon insulating plates1 e and e4 ,fusible mica-foils1 g1 and switch plates1 h and i1 with plugs k1 are provided for protecting and disconnecting the circuits4 ,the open front of the compartments ,d and ,d are closed by glass plates1 ,t1 which permit inspection of the connections without entering the box4 ,the converter box occupies little space1 and may be placed in any convenient situation in or about the premises to be lighted1 much the same as a gas-meter4 ,the practice where overhead conductors are employed1 is to mount the converter box on a pole in the vicinity of the premises to be lighted1 as shown by ,fig4 #ac1 and thus it is only necessary to lead the secondary or low potential wires into the building1 the high potential wires remaining in an accessible position upon the pole4 ,fig4 #ad is a view of ,north ,street1 ,pittsfield1 ,massachusetts1 engraved from a photograph1 and shows a very neat form of tubular pole with its converter box on top4 ,this arrangement is used throughout the city1 and is a great improvement on the ordinary form of telegraph poles which so greatly disfigure ,american cities1 and are really the most objectionable feature of the overhead wire system4 ,illustration3 ,fig4 #ab4 ,illustration3 ,,fig4 #ac4 ,illustration3 ,,fig4 #ad4 ,to face page #cg4 ,the potential ordinarily employed in the main circuits of the ,westinghouse installations is about #ajjj volts1 and that in the lamp circuits #ej volts1 the ratio of conversion1 therefore1 being as #bj to #a2 the dynamos are manufactured1 as a rule1 in three sizes1 ,no4 #a for #fej1 #af candle-power lamps2 ,nos4 #b and #c for respectively #acjj and #bejj lamps4 ,the converters are also made in three ordinary sizes to supply #bj1 #cj1 and #dj lamps of #af candle-power each4 ,a #dj-light converter contains about #he pounds of iron and #be pounds of copper1 so that the total weight of metal is less than #c pounds per lamp2 the electrical efficiency of the converter is said to exceed #ie per cent4 when the potential is reduced from #ajjj volts in the primary to #ej in the secondary4 8,it is claimed that the trifling loss of energy in conversion from high to low potential at the point of consumption is made up for by gain at other points1 especially in the increased efficiency of the lamps1 so that an alternating current plant may be counted on to give #aj-af candle-power lamps per indicated horse-power1 as against #g with the direct system20 the comparative gain is doubtful1 but by using #ej instead of #ajj volts the life of the lamps is increased1 the former having a much stronger filament and consequently a longer life4 ,,electric ,,motors4 ,having slightly diverged from the original lines by describing a system which is at present not introduced into ,europe1 a few remarks on the subject of electric motors may not be inappropriate1 as they are almost universally worked in the ,united ,states1 from the installation which supplies electric light4 ,there is a considerable profit to the electric company if electric power is taken in the district1 the wires conveying the lighting current are thus economically employed during the day4 ,in the diagram1 ,fig4 #ae1 which represents a district at ,boston1 the curve on the right principally represents the demand for power which takes place between the hours of #h ,a4,m4 and #c ,p4,m4 ,a circular was addressed to all the leading electric companies in ,america a short time ago1 asking if they supplied power as well as light1 also for what purposes it was used4 ,answers were received from #ef companies1 who stated that the motors were employed for3--driving ventilator fans1 collar-and-cuff machines1 printing-presses1 various apparatus in repair-shops1 sewing-machines1 coffee-mills1 gun-shop tools1 sausage-machines1 elevators1 lathes1 pumps1 saws1 ice-cream freezers1 organ-bellows1 and washing-machines4 ,the size of motors varied from one-eighth to #ae horse-power2 #bf companies have supplied motors from arc light circuits1 #ad from arc and incandescent1 and #af from incandescent circuits alone4 ,the motors are principally owned by the subscribers1 and are charged for at a rate varying from #c to #ae per horse-power per month4 ,the motor business is still in its infancy1 but is cited to show how ,electric ,power can supplant the steam-engine1 especially for those purposes in which the power required is small and complete control is desirable4 ,illustration3 ,,fig4 #ae4 ,,class ,,ii4 ,,the ,,edison ,,parallel ,,system1 ,,with ,,continuous ,,current4 ,it will be found1 on examining ,appendix ,,ii41 that in ,european stations by far the larger number of lamps are maintained from installations employing the ,edison system2 the ,ferranti plan of using transformers comes next1 closely followed by ,goulard and ,zippernowsky2 the distribution with secondary batteries follows1 and the high-tension multiple series comes last4 ,illustration3 ,,fig4 #af4 ,the ,edison system has frequently been discussed1 in connection with small installations1 but in magnitude the stations in ,berlin and in ,milan exceed anything that has been started here with continuous current4 ,before describing the central electric light station at the former city1 it may be well to recall to mind that the ,edison plan is the combination of a number of machines which pump electricity into a network of feeders1 mains1 and conductors1 the lamps being placed in parallel circuit1 as shown at ,l l1 ,fig4 #af1 and maintained at a constant potential of #aaj volts4 ,illustration3 ,,fig4 #ag4 ,m ,m are the flow and return mains1 the dynamos bridging them across at one end4 ,if the mains were very long1 those near to the dynamos would be exhausting the supply1 and the lamps at the remote end would not get the full pressure4 ,a system of feeders has been devised so that each lamp1 no matter where it may be1 shall have approximately the full #aaj volts working through it4 ,fig4 #ag shows a long circuit consisting of two branch mains bridged by a large number of lamps1 l l1 and ,d ,d are the dynamos at the central-station4 ,series of feeders1 f f1 have to be taken from the dynamo mains and fed direct into the branch mains at various points1 d d1 b b1 c c1 in order to distribute the electrical pressure equally4 ,,the ,,three-,,wire ,,system4 ,the ordinary parallel system is undoubtedly suitable for small installations2 but when the area to be lighted is extensive1 it is impossible to proportion the mains1 with a view to economy in the cost of copper1 without sacrificing energy wasted in heating the conductors4 ,in ,figs4 #af1 #ag1 the lamps are shown in simple parallel2 but if two dynamos are connected together1 and a main wire is run from each of their two extreme terminals and a third wire from the branch connecting the two machines1 we have what is known as the three-wire system1 which was invented by ,edison in ,america1 and ,hopkinson in ,england1 almost simultaneously4 ,although by using the third wire there is a saving in copper over the parallel plan1 the maximum gain is not more than #be per cent41 under the best conditions2 when the district to be illuminated is not more than #djj to #fjj yards from the central-station1 the three-wire system answers well1 but as soon as this distance is exceeded the cost of the mains begins to mount up at a most alarming rate4 ,although there are many ,edison installations in the ,united ,states on this system and a few on the ,continent1 it has only been used here in a few instances for factory lighting4 ,,the ,,edison ,,system ,,at ,,milan4 ,the ,santa ,radegonda station at ,milan is at the present moment the second largest ,edison station in ,europe4 ,the building1 which was formerly a theatre1 is well adapted for the work required2 the dynamos and engines are fixed in a deep basement1 while the boilers are a few feet above the street level1 the upper floors being used as stores and testing-rooms4 ,the dynamos1 eight in number1 are of the old ,edison type1 with horizontal magnets2 seven of these machines are connected to the feeders which supply the mains1 and these cover the district to be lighted on the ,edison network system4 ,the motive power is furnished by six ,armington-,sims1 and two ,porter-,allen engines1 each connected direct to the armature of a dynamo1 the speed being maintained at the uniform rate of #cej revolutions per minute1 except in the case of the spare engine and dynamo1 which is kept turning slowly1 ready to be switched on should occasion demand4 ,the starting or cutting-out of circuit of these large machines requires some care4 ,in the first place1 to start1 it is necessary to insert resistance into the shunt circuit of the dynamo1 which is done by a switch2 but to throw #aej horse-power into the main circuit would be dangerous to the lamps1 so that the current is first sent into a bank of one thousand lamps used as a resistance1 and these are cut out step by step2 similar care is taken when a machine is stopped4 ,to control the electro-motive force1 which varies greatly from time to time1 hand regulation is used during the day1 with the help of the ,edison tell-tale1 consisting of two lamps1 a red and white one1 which light up when the current is high or low2 but when the night service comes on1 as it may happen that two thousand lamps may be turned out at once1 an attendant has to carefully watch the electric regulator1 and be ready to insert resistance into the field-magnet circuits by moving a wheel connected by a shaft and bevel-gear to a system of commutators4 ,the principal difficulty to be overcome1 in an installation where the current is distributed over a large area1 is the regulation of the electro-motive force at the various points1 as at ,milan2 there are no return galvanometer wires1 which are now used in both the two and the three-wire ,edison systems in the ,united ,states4 ,the plan devised by the company's electrician at ,milan is very ingenious1 and enables the pressure at the ends of the various feeders to be kept practically the same1 although they are of different lengths and sectional area4 ,in the first place1 resistance was added to each feeder to equalise the resistance in each conductor2 and1 in order to provide for the varying amount of current the feeder has to supply1 a peculiar form of commutator1 having a guillotine-shaped contact-piece1 was inserted in the circuit4 ,by moving this1 suitable resistance is inserted or cut out1 and the attendant1 having a series of numbers1 has only to set this instrument to the number shown by the ampre meter4 ,by far the largest amount of current is drawn off for the lighting of the ,scala ,theatre1 the stage-lighting alone taking more than one thousand lights3 if these were all turned on suddenly1 the other lights in the district would be dimmed2 to obviate this1 auxiliary feeders have been run1 which are used only when any great increase is expected2 commutators similar to those referred to above also regulate these feeders without any special attention4 ,the pressure at any point in the system is by this means easily controlled1 and affords an illustration of what is perhaps not the most economical1 but is found to be the most practicable1 way of maintaining a constant potential in a district where the amount of output of current is suddenly doubled4 ,fig4 #ah is a plan of the network system of conductors laid through a large portion of the city2 the conductors are in outward appearance similar to gas-pipes1 the current passing through semicircular bars of copper1 embedded both for the flow and return in the same iron tube1 which is laid underground in a shallow trench4 ,the house-supply is drawn from the mains1 and these are connected to the feeders by means of ordinary junction-boxes1 which each contain a fusible cut-out4 ,the bridge-boxes allow of expansion of the line1 and have connections for testing purposes4 ,the insulation is extremely good1 mainly on account of the favourable nature of the ground1 which is chiefly gravel2 no trouble has been experienced with leakage1 nor has the service ever been interrupted4 ,the cut-outs are of an improved ,edison form1 but have the disadvantage attending all lead plugs where the current is great1 in that1 to guard against accidental melting due to the heating effect of the current1 the sectional area of the lead has to be much larger than would be otherwise necessary4 ,in fact1 these cut-outs will protect the cable against a bad short circuit1 but nothing else4 ,illustration3 ,,fig4 #ah4 ,in addition to the glow lamps1 eighty arc lamps are worked in derivation1 two in series2 most of these lamps require #de volts1 to which #aj per cent4 of idle resistance is added1 constituting a total loss of current which is extremely low for a combined arc and incandescent system of lighting4 ,the service commenced in #ahhb with a little over one hundred lamps1 and at present there are over ten thousand glow lamps1 and two hundred arc lamps are in use4 ,at first the new enterprise had to struggle against very great difficulties2 not only the technical difficulties of distribution by means of a network of feeders and mains had to be overcome1 but also those arising from the prejudices of consumers and the competition of the gas company1 who tried to deter consumers from introducing electric light into their houses4 ,one of these means consisted in offering to the private consumers1 resident in the district which was threatened by competition with electricity1 an agreement by which the gas company bound itself to supply gas at #es4 #h;d4 per #ajjj cubic feet1 instead of #gs4 #g;d4 as charged hitherto2 and even now those inside the 8charmed circle0 of the electric light conductors get their gas cheaper than the public outside4 ,one of the reasons which accelerated the adoption of electric light was the introduction of the ,edison meter1 in consequence of which consumers could be charged exactly for the amount of light they had received1 and were relieved from paying a lump sum according to the number of lamps fixed1 which was customary in the early days of the company4 ,the prices at which the company now provides light1 at all hours of the day and night1 are as under3-- ,installation ,charge per ,type of ,lamp4 charge per lamp4 lamphour4 s4 d4 #aj-;candle #ah #jbf #af- 0 #bh #jdj #cb- 0 #ef #jhj that is1 a little over d4 per ampre-hour2 the #aj-;candle lamps requiring #je1 the #af-;candle lamps #jge1 and the #cb-;candle lamps #ae ampre4 ,the company lends meters for #ej1 #ajj1 and #aej lamps1 at an annual rent of #ds4 #aj;d41 #gs4 #c;d41 and #is4 #g;d4 respectively1 and replaces1 without charge to the consumer1 any lamp the filament of which has broken1 but it does not replace lamps where the glass is broken4 ,for arc lamps requiring #i to #aj ampres1 an annual rent of #b must be paid for the lamp itself1 and a charge of a little over d4 per hour for every ampre-hour4 ,the carbons are charged for at #a;d4 per pair1 lasting for about seven hours4 ,now that the installation has been in use for several years1 and that the company has arrived at a very accurate estimate of the time during which an average consumer requires the light--about one thousand six hundred lamp-hours per annum--it proposes to simplify the method of charging large consumers1 by omitting the initial charge of each lamp1 and1 instead1 to charge #jf;d4 for each #af-;candle lamp-hour4 ,the ,edison meters are based on the electrolytic action of a small fraction of the current which passes through the meter4 ,they are cells1 with rectangular zinc plates immersed in a solution of sulphate of zinc of #ajed density1 the distance between the plates being a little over inch4 ,the proportion of the current which passes through the meter to that which passes directly into the consumer's house is #a to #igc4 ,the resistance of the shunt circuit is #ige ohms1 made up as follows3 cell1 #age ohm2 metallic portion1 #h ohms4 ,the resistance of the metallic portion rises with the temperature1 whereas that of the cells falls with a rising temperature2 and in this manner the small variations of resistance which might take place in the cell are counter-balanced by the equally small variations in the resistance of the metallic portion4 ,a complete meter consists of two similar-sized cells of the same resistance1 placed in series4 ,the object of employing two cells is1 that when little current is passing1 as in the summer months1 one cell alone is used1 and when the consumption is sufficiently large both cells are employed1 and the mean between the two indications is taken as the basis for calculation in number of ampre-hours4 ,the quantity of electricity passed through the cell is calculated by the loss of weight which has taken place in the positive plate4 ,an employ of the society visits every meter monthly1 taking away the old cells and substituting others freshly constructed4 ,a book is kept in which the weights of the new plates and those of the returned plates are entered1 and on the basis of these entries the accounts are made up4 ,the largest plates are those in the #ajj-light meter1 and are intended for a maximum current of #ge ampres in the main circuit2 they are #f inches long by #b inches wide4 ,in cases where a larger amount of current is taken1 the capacity of the #ajj-light meter is increased by joining two or more copper strips across the terminals of the cells4 ,the weak point of the system is the removal of the cells1 which leaves the adjustment of the account to be paid entirely in the hands of the ,electric-,light ,company2 in spite of this drawback1 it is stated that there has not been a single complaint from consumers during the four years in which the meter system has been in use4 ,discovery of ,faults4 ,it is evident that in so extensive a system of lighting a short circuit now and then between the lamp wires and the earth cannot altogether be avoided4 ,many of the lamps have been fitted to existing gas fittings1 and are beyond the daily supervision of the company's officers2 the faulty place is often not easily accessible1 so the first step taken is to discover on which of the two circuits the trouble has occurred4 ,this is done at the station by joining two #af-;candle lamps in series across the main conductors and the point of junction between the two lamps is connected to earth by a stout wire4 ,as long as both circuits 7positive and negative7 are perfectly insulated from earth no current flows through this middle wire1 and both lamps remain hardly incandescent2 but1 if one of the circuits should be in connection with the earth1 the lamp which is joined on the other circuit will brighten up1 because the potential of the middle wire and that of the faulty circuit are both zero1 and consequently the lamp between the middle wire and the sound circuit receives the full pressure of #aaj volts4 ,to localise the fault1 contact is made between the earth and the sound circuit by means of a fusible plug of known melting point1 say for a thirty-lamp supply4 ,if the fault is on a portion of the external circuit1 supplying less than thirty lamps1 its fusible plug will melt as soon as the sound main is put to earth4 ,if1 however1 the fault is on a portion supplying more than thirty lamps1 the fusible plug which has been inserted at the station between the sound main and the earth will melt instead4 ,a series of fusible plugs are thus tried1 increasing in melting capacity until one is found that does not go3 in this case1 the other plug on the faulty portion has melted1 and the consumer's lamps on that branch are extinguished2 the position of the fault is thus localised1 and the company proceed to remedy the defect without interfering in the slightest degree with the rest of their system4 ,,the ,,electric ,,lighting ,,of ,,berlin4 ,the ,edison system is also employed at ,berlin1 in fact the ,deutscher ,edison ,gesellschaft have at the present time a monopoly of the supply of the city from three large central-stations1 each of which serves the area in their immediate neighbourhood4 ,the mains differ from those used at ,milan in that stranded highly insulated cables1 protected with steel wire on the outside1 are laid under the pavement in every street throughout the district4 ,with the exception of the ,leipziger strasse and ,unter den ,linden1 which are lit with arc lamps suspended from chains running between cast-iron poles #bd ft4 high1 about #ajj to #bej ft4 apart1 gas is used for the street lighting1 and electricity for the interior illumination of many public buildings and private houses2 there are also a good many arc lights outside the shops and restaurants4 ,the mains are on the ,edison network system1 the area of copper being such1 that when all the lamps are on there is a loss of energy of #be per cent42 but this does not occur on an average for more than half an hour a day4 ,no sole concession is given to the company1 who simply have the right to take up the pavement and cross streets1 and for this permission they are bound to furnish any consumer in the district with a constant supply of electricity at the following charges3-- #aj-;candle lamps #be pf41 about #jbi d4 per hour4 #af- 0 #dj 0 #jdh 0 #cb- 0 #hj 0 #jif 0 #ej- 0 #abe 0 #aej 0 #ajj- 0 #be 0 #cjj 0 ,in addition to this an installation fee of #fs4 per lamp is charged1 which includes one lamp4 ,meters are charged as follows3-- s4 d4 #aj- to #af-;candle-power #j #af #j per annum4 #be- 0 0 #a #j #j 0 #ej- 0 0 #a #aj #j 0 #ajj- 0 0 #b #j #j 0 ,a discount is allowed off this meter charge1 varying with the number of hours the light is used in the year4 ,the cost of gas is about #ds4 #i;d4 per #a1jjj cubic feet1 so the electric light is slightly the dearer illuminant4 ,the ,aron meter1 ,fig4 #ai1 is usually employed as the recorder of the electricity consumed4 ,it consists of two pendulums1 controlling two distinct clockwork gears4 ,one oscillates at a regular speed1 but the other has a permanent magnet1 instead of a weight1 and is variable in speed4 ,the entire current passes through the solenoid1 which is underneath the pendulum1 with the magnet2 the difference in speed between the standard and variable clocks is given in direct ampre-hours by a counter-gearing similar to the index of a gas-meter4 ,an electro-magnet starts each pendulum when the current begins to flow1 and immediately it ceases1 two detents come into operation and hold the pendulums stationary4 ,illustration3 ,,fig4 #ai4 ,,class ,,iii4 ,,the ,,series ,,system ,,of ,,distribution4 ,this method dates back to the introduction of the incandescent light1 and1 although it has been frequently demonstrated that a small current of high potential could be employed to work incandescent lamps1 the series system has never been installed on a commercial scale1 and is confined to arc lighting4 ,in the ,united ,states the usual pressure for arc lighting is #b1jjj volts1 and it is not an uncommon occurrence to have forty arc lamps in series upon a line over #aj miles in length1 carrying a current of #aj ampres4 ,to economically use this high pressure for glow lamps in series1 they must be of such design as to enable the whole of the current to be passed through them without injury4 ,the filament of an ordinary high-resistance glow lamp would be immediately destroyed1 so that low-resistance lamps1 having a much larger sectional area1 must be employed4 ,the ,bernstein or the ,cruto lamp1 which can be made to have a 8hot0 resistance of about #jg ohm1 and requires a current of #ige ampres1 could be used1 and the current might be economically brought from a great distance4 ,mr4 ,bernstein calculates that it would be possible to operate #f1jjj of these #g-volt lamps from twenty dynamos1 each giving a current of #aj ampres at a potential of #b1jjj volts1 and still have a margin for loss of current in the leads4 ,an economical feature of this scheme is the easy way in which power could be saved when only comparatively few lights were required2 for instance1 in the daytime all the circuits could be looped together and fed by one dynamo1 and1 as the number of lights increased1 so other machines could be switched in by having an auxiliary bank of lamps as a resistance4 ,from the central-station twenty pairs of carefully insulated copper wires1 say of ,no4 #f ,b4 ,w4 ,g41 would lead to the houses2 and1 as a good-sized ordinary house takes on an average twenty lights1 the conductor would pass through fifteen houses before it returned to the station4 ,it is in the house that the practical difficulty commences1 as in this series system the circuit must never be opened1 so that the switches and safety appliances must be such that1 whatever happens1 there must remain some path for the current1 otherwise all the lights on that particular circuit would be extinguished4 ,mr4 ,bernstein gives the designation of 8short closed0 if the current goes through the switch-lever1 and 8long closed0 if the current is led through the lamps or other electrical devices4 ,illustration3 ,,fig4 #bj4 ,fig4 #bj is a diagram of the lamps in any building4 ,the street main1 ,m1 enters at the main switch1 ,s1 and continues from switch to switch1 ,s ,s1 and returns to ,s before it leaves4 ,it is necessary1 to guard against any possible extinction1 to construct all the switches so that it would be impossible to move the lever without a lamp was lighted2 and1 should the lamp give out1 an equivalent resistance must be automatically inserted4 ,these details have been investigated by ,mr4 ,alexander ,bernstein1 who has designed a complete system for 8series0 lighting1 and claims for it special economical advantages4 ,it is1 however1 very doubtful if this plan can be recommended for adoption in private houses2 but in public lighting1 or in large establishments where an electrician could be kept to look after the fittings and the insulation of the conductors1 there should be no more danger1 in introducing the high-tension continuous current of #b1jjj volts1 than there is at present with the #ajj-volt alternating current1 and the relative saving in weight of conductors would be an important item4 ,installations on this method have been erected at ,messrs4 ,brunner and ,mond's alkali works1 and in several large factories in the ,united ,states where lights had to be distributed over a considerable area2 the system has not1 however1 come into favour for central-station work4 ,,class ,,iv4 ,,the ,,multiple ,,series ,,system4 ,this method of using a high-tension current has already been referred to in connection with house-to-house lighting at ,brighton1 it was first employed for the street lighting of ,chesterfield by the ,brush ,company4 ,the electric lighting of the town of ,temesvar1 in ,hungary1 is on a far larger scale1 and has1 from ,november #ahhd1 successfully superseded a combination of gas for the more important streets1 and petroleum for the outlying ones1 the total cost of which was #bf1dhj florins per annum4 ,a twenty-four years' concession was given to the ,international ,electric ,company1 the plant remaining their property at the expiration of the term1 subject to purchase by the municipality at their own valuation4 ,the public lighting is stipulated to be effected by means of #gca glow lamps of the intensity of #af candle-power2 but the option is given to the company of switching out a fixed proportion of these lamps at #aa4cj ,p4,m41 or of leaving the whole number in operation with their light-intensity reduced from #af to #h candle-power from #aa4cj ,p4,m4 till dawn4 ,the total number of lighting hours per annum is #c1eig for the lamps which are in operation from dusk until dawn1 and #a1haf for those which are extinguished at #aa4cj ,p4,m4 ,the price fixed in the concession for public lighting is #ae kreutzer per #af candle-power lamp per hour1 equal to #ec florins #ie kreutzers per lamp per annum of #c1eig hours1 or #bg florins #bd kreutzers per lamp per annum of #a1haf hours4 ,the company has found it more convenient to exercise the option reserved to it1 of keeping all the #gca lamps in operation from dusk till dawn1 reducing their light-intensity to #h candles after #aa4cj ,p4,m42 and the municipality has agreed to pay a round sum of #bi1jjj florins 7#b1daf #acs4 #d;d47 per annum for this lighting1 and #daie florins 7#c #ajs47 per annum for each additional lamp worked in the same way4 ,comparing these figures with what precedes1 it will be found that the electric lighting of the streets now in operation costs #b1ebj florins more than it did on the former plan of combined lighting1 partly by gas and partly by petroleum4 ,on the other hand1 the streets are lighted throughout with #af candle-power lamps from dusk until #aa4cj ,p4,m41 and with #h candle-power lamps from #aa4cj ,p4,m4 until dawn4 ,for electric light supplied to private consumers the concession fixes the price at #aha kreutzers per #af candle-power lamp per hour1 or #jaaca kreutzers per candle per hour1 with the right to charge #ae per cent4 more for lamps of less intensity than #af candles4 ,in all these prices the renewal by the company of lamps failing from legitimate wear is included4 ,illustration3 ,,fig4 #ba4 ,,multiple ,,series ,,lighting4 ,,temesvar4 ,one central generating station has been provided for the whole town1 from which at present four distinct circuits have been laid1 each fed by a separate dynamo4 ,the street lamps are connected up in 8multiple series10 that is to say1 in groups placed in series on the circuit1 the lamps in each group being connected up in parallel4 ,fig4 #ba shows the arrangement diagrammatically4 ,each group consists of eight lamps in parallel2 at present three of the circuits have twenty-four groups in series1 and the fourth circuit has twenty-three groups in series1 giving a total of ninety-five groups1 comprising #gfj lamps1 of which #gca are public lamps and #bi are used at the central station4 ,to meet the risk of interruption in any circuit through the failure of individual lamps1 an automatic switch is arranged so as to put in a reserve lamp1 in the event of a whole group being interrupted4 ,another self-acting device will short circuit the whole group1 so that the other groups in the circuit will be unaffected4 ,the automatic lamp-switch is contained1 together with the reserve lamp1 in the lantern1 and the automatic group cut-out consists simply of an electro-magnet with a coil of high-resistance connected up in parallel with the group of lamps it protects4 ,these appliances have been found to work well4 ,the main conductors are formed of insulated single copper wire1 #df millimetres in diameter2 they are carried overhead on porcelain insulators1 fixed to telegraph posts or to wooden arms let into the walls of houses2 the resistance of this conductor is about #aa ohm per kilometre4 ,the glow lamps are placed in reflectors at an angle of about #de from the vertical1 and are carried on brackets either fixed to the walls or on special cast-iron posts4 ,fig4 #bb shows the details of street bracket and reflector with automatic lamp-switch and lamps in place4 ,the brackets are for the most part fixed to the walls of houses or to painted wooden posts4 ,illustration3 ,,fig4 #bb4 ,,lamp ,,bracket4 ,the under side of the reflector1 which is made of enamelled iron disposed in the form of a flat inverted cone1 reflects the upward rays from the lamp and causes the extreme ones to strike the ground at a distance of about #ej metres from the foot of the lamp-post4 ,the increase of lighting effect in the streets due to those reflectors is very marked4 ,the upper part of the reflector serves the purpose of a case and weather protector for the automatic lamp-switch which is inserted from the top1 and the lower end of which is fitted with copper hooks to which the two lamps are fixed4 ,the glow lamps are fitted with holders of a type designed by the engineer1 which provide the lamp terminals with large and strong eyes affording considerable contact surface and adapted for hooking on direct to #be mm4 copper wire1 the ends of which have merely to be bent into a suitable form for maintaining the lamp in any required position4 ,these lamps are of an improved ,lane ,fox type1 manufactured by the ,electrical ,company1 at their works in ,vienna4 ,although originally intended for #af candle-power lamps they have so far been worked at #ah candle-power1 taking #ecfah volts and about #aahc ampres1 which is equivalent to #cebb watts per candle-power1 or about #baa candles per horse-power4 ,the current is maintained at #aj ampres1 and the potential between independent groups of lamps is #ecf volts4 ,the aggregate energy lost1 in overcoming the resistance of the main leads1 switches and cut-outs1 is #abh per cent1 of the total electrical energy generated at the central-station--a very satisfactory result on a system of over #cg miles of streets4 ,the electro-motive force in the conductors is about #a1djj volts1 which is below the normal capacity of a ,brush machine1 thus allowing more lamps to be operated from the four machines4 ,the machinery is driven by a #cjj horse-power horizontal compound-condensing tandem steam-engine1 running at the normal speed of #ajj revolutions per minute4 ,during the first #a1bjj hours of lighting1 only three lamps out of #gfj failed1 and one of these had been broken maliciously4 ,the engineering arrangements are due to ,mr4 ,c4 ,f4 de ,kierskowski ,steuart1 ,m4 ,inst4 ,c4,e41 the various difficulties incidental to a novel work having been surmounted with experienced workmen4 ,although the system at ,temesvar has more complicated arrangements than are now required if secondary generators are used1 it has shown that it is quite practicable to light all the streets in a town by electricity2 also it has enabled a comparison to be made between the useful effect obtainable from arc and from glow lamps4 ,each group of glow lamps was found to absorb practically the same energy as one arc lamp of from #hjj to #a1jjj candle-power1 and ninety-one or ninety-two of these could have been run with the same expenditure of power as #gca glow lamps4 ,the eight glow lamps forming one group are in many cases scattered in different streets1 often quite out of sight of each other4 ,under such circumstances1 the substitution of one light centre1 however powerful1 for every eight could only be done by leaving many spots in complete darkness4 ,to give a usefully diffused light by means of arc lamps1 their number would have to be considerably greater than ninety-two1 or1 in other words1 the standard of street lighting would have to be raised1 and for this the town was not prepared to pay4 ,the business has now passed into the hands of the ,anglo-,american ,corporation of ,london1 who are extending the installation by placing alternating current dynamos at the station to work transformers for the supply of houses so as to utilise the original plant for street lighting only1 as1 even with the advanced knowledge of the present day1 it is doubtful whether for this purpose a more economical system could be employed4 ,,class ,v4 ,,the ,,distribution ,,with ,,secondary ,,batteries1 ,,or ,,the ,,battery ,,transformer ,,system4 ,mr4 ,lane ,fox was the first to put forward a complete system of electrical supply on this plan1 ,fig4 #bc4 ,illustration3 ,,fig4 #bc4 ,g ,generating station4 ,a ,accumulators 7secondary batteries74 ,r ,returns4 ,m ,mains or conductors4 ,l ,lamps4 ,x ,meters4 ,the system is discussed by him as follows3#d-- 8,the chief points of the system is the use of a generator in a central position1 from one pole of which insulated conductors or mains are led to the several points where the electric energy is to be utilised1 being branched and sub-branched as much as required1 and thence back to the other pole of the generator by an uninsulated conductor1 such as the gas or water pipes4 ,at certain points1 storage or secondary batteries are set up in connection1 on one hand1 with the mains1 sub-mains1 and branches1 as the exigencies of the case may require1 and1 on the other1 with the return conductor40 #d ,hedges on the ,supply of ,electricity by ,local ,authorities4 ,proceedings of ,association of ,municipal and ,sanitary ,engineers and ,surveyors1 vol4 ix4 7#ahhb-hc71 p4 #aei4 8,the combination of generators1 circuit and storage batteries is such1 that when the current from the generators falls below the demands made on it from the various outlets to the mains at which its energy is utilised1 the deficiency is made up from the storage batteries1 which act in unison to supply the requisite quantity of energy4 ,on the other hand1 when the current from the generator exceeds in point of quantity the demands upon it at the various outlets1 the excess goes to charge the storage batteries and to create a reserve to be called upon in case of need40 ,the objection to the system which prevented it being put in practical operation was the use of the earth as a return conductor4 ,besides the great danger of short circuit1 the gas and the water pipes1 which are so thickly laid in most cities1 would conduct the current and interrupt telegraphic and telephonic communication4 ,the experiment of using storage batteries as reservoirs1 from which a constant supply of electricity could be drawn as required1 was tried on a considerable scale at ,colchester1 where a large installation was started in #ahhd1 secondary batteries being placed in favourable positions1 and charged by a high-tension current4 ,the plan adopted is shown by ,fig4 #bd4 ,illustration3 ,,fig4 #bd4 ,a is a meter in charging circuit2 ,b1 the batteries or accumulators2 ,l1 lamps in parallel on low-pressure service main4 ,the dynamos were two of the ,brush type1 each dynamo giving a current of #ie ampres1 with an electro-motive force of #a1hjj volts1 when rotated at a speed of #gjj revolutions per minute4 ,they were driven by a semi-portable engine indicating #ij horse-power4 ,the dynamos were coupled in parallel circuit for quantity1 and excited by a small machine giving #aj ampres4 ,the current was led some distance by a seven-strand #ai ,b4 ,w4 ,g4 cable to the batteries1 which were charged in series1 the #fj-volt lamps being placed in parallel on separate mains connected to the batteries4 ,the danger of introducing a high-tension current of #a1hjj volts into the houses was obviated by a rocking-switch worked automatically1 so as to throw the batteries out of the charging circuit4 ,the operation was accomplished by means of a master cell ,m1 ,c1 ,fig4 #bd1 similar to the others1 but fitted with an arrangement to collect the gas evolved1 which extended a diaphragm attached to a make-and-break arrangement which worked the rocking-switch4 ,the ,colchester installation did not turn out commercially successful1 and has been abandoned2 but the experiment has been valuable1 and there is little doubt that1 with simplification of details1 a high-tension charging current could be led from a dynamo fixed in any convenient site where power is available2 also in very crowded districts the batteries could be placed in cellars and be drawn from as reservoirs1 so as to furnish a constant supply of electricity4 ,illustration3 ,,fig4 #be4 ,to face page #fi4 ,the ,kensington ,court installation has been previously quoted as an example of what promises to be one of the most successful methods of distributing a constant supply of electricity through a large area1 a description of the station may therefore be interesting4 ,the accompanying elevation1 ,fig4 #be1e shows the unpretending design of the building1 and the very compact arrangement of the generating machinery and batteries4 ,when the illustration was made the plant consisted of one ,willan's single-crank triple-expansion engine in combination with a ,crompton dynamo provided with vertical inverted single magnets1 the output being #bej ampres at #adj volts when running at #ejj revolutions per minute1 the steam pressure being #afj lbs4 on the square inch4 ,a complete duplicate plant has already been installed1 and three more sets of engines and dynamos are shortly to be erected4 ,the draught from the boiler is led downwards by an underground flue1 with the object of economising the very limited space as much as possible4 ,as a rule1 the dynamo and accumulators are used in parallel1 the current enters and leaves the regulating cells by the same contact1 in other words1 there is only one switch which serves for charging and discharging the batteries4 ,this switch has nine contacts1 so as to give nine degrees of regulation of the light2 when the dynamo and accumulators are working together1 the lights are parallel with either #da1 #db1 or #dc cells1 according to the amount of charge in the cells and current required1 while1 when the dynamo is out of circuit1 the lights are worked off1 #ej1 #ea1 #eb1 or #ec cells4 ,the current passes through the usual measuring instruments1 and each main conductor is protected by safety fuses mounted in a ,hedges duplex cut-out4 ,the accumulators are of the ,plant type1 but instead of being plain lead are sawn out of ingots which are cast porous on the ,howell process4 ,each cell contains #ce plates1 #h in4 #h in41 and1 as each plate when fully formed is said to be capable of yielding five ampre-hours per pound of lead1 the cell has about #fjj ampre-hours total capacity4 ,in the event of a serious breakdown the whole of the work would fall on the accumulators1 which could furnish a steady current for perhaps an hour or more2 and herein lies the novelty of the arrangement4 ,for the first time we have an accumulator put in not only as a fly-wheel to the whole system and to give the advantage of supplying current throughout the day and the small hours when the engine is not running1 but also to act as an actual reserve4 ,the routine is as follows3--the dynamo will start charging the accumulators a few hours before dusk2 for a short time after lighting hours commence1 the dynamo alone will supply sufficient current1 but later on the demand will gain on the dynamo1 and a certain portion of the discharge will be from the accumulators4 ,at eleven o'clock at night the engine will be stopped and the accumulators will alone supply the demand for the rest of the night4 ,in the small area occupied by the station there is ample room for a plant of six times the present capacity1 and it is intended to erect sub-distributing stations at points at the outskirts of the district where accumulators to act as transformers will be fixed1 which will be charged by a special main with a current of #ejj volts1 the outgoing wires from the sub-station taking electricity at the usual ,e4,m4,f pressure for incandescent lamps in houses of #ajj volts4 #e ,from ,industries4 ,thirteen candle lamps are used in the district1 having been found to be more convenient than #af or #bj candle-power1 the #ac candle is obtained for #cf watts1 or #bge watts per candle4 ,the price charged to consumers is #h;d4 per ,board of ,trade unit1 or equivalent to gas at about #ds4 #g;d4 the #a1jjj cubic feet4 ,meters on the ,aron plan1 ,fig4 #ag1 are used1 a card being supplied on which the readings are entered exactly similar to the method adopted with gas4 ,the service mains terminate at the meter1 where the company fix for their own purposes a double pole switch of the author's design1 ,fig4 #bf1 which enables both wires to be disconnected1 a spring shut-off1 marked ,s ,s1 prevents the switch being left partly on4 ,,system ,,of ,,distribution4 ,the mains from the ,kensington ,court ,station are laid underground in a culvert #ah in4 by #ab in41 which is built with brickwork and cement under the pavement4 ,a double conductor of flat copper1 #jbe square inches section1 is stretched from shackle insulators attached to iron bars1 which are firmly built into the culvert2 the continuity of the circuit is provided by means of stranded wire1 which connects each section2 the flat copper rests on the top of porcelain insulators1 fixed on vertical iron pieces1 which are built into the floor4 ,connections with the sewers are left for drainage1 and six surface boxes are provided for every hundred yards4 ,where house connections have to be made1 the branch wires are united by soldering to the bare copper mains4 ,for crossing under the streets a heavily insulated cable is employed1 and is led through cast-iron pipes4 ,illustration3 ,,fig4 #bf4 ,until a larger amount of mileage is actually at work1 it is difficult to express an opinion as to which is the cheapest and most efficient method of laying conductors in the streets4 ,the relative cost of two plans tried at ,kensington ,court--the insulated and the bare cable in a culvert--was given by ,mr4 ,crompton in the following ,tables1 ,no4 #a and ,no4 #b1 which are taken from a paper read before the ,society of ,telegraph ,engineers and ,electricians on ,april #abth1 #ahhh4 ,table ,no4 #a refers more particularly to what is known as the ,callender-,webber system of using bitumen concrete1 which is compressed into blocks or cases usually about #f ft4 long1 #h in4 by #e in4 section1 having two-inch holes through which the insulated copper cable is led4 ,the estimates given in ,table ,no4 #b were criticised by ,mr4 ,kapp1 who thought that 8a more reliable conductor could be obtained by using a high-class lead-covered cable1 which might be laid in the ground with the simple protection of a rough tarred plank to cover it40 ,the cost of digging the trench and running in the cable from the drum was quoted at #cs4 a yard1 and the total cost1 inclusive of #aj for surface boxes1 at #aee per #ajj yards1 instead of #ahg1 as shown by the ,table4 ,,table ,i4 ,cost of ,laying #ajj ,yards of ,double ,conductor underneath the ,footway of a ,london ,street4 ---------------------------------------- ---------------- ,single4 #g_/af #ai_/ae ,no4 #af4 ---------------------------------------- ---------------- ,area1 square inch #jjcb #jbbe #jggc ,area1 square millimetre #bjh #adf #ej ,weight per #ajj yards run lb4 #g #ec #ahc ,cost of copper at #g;d4 #j #d #aj #a #ad #f #e #ah #j ,cost of insulation #a #c #b #d #h #faa #b #j ------------------------- ,total cost of ,cables #a #h #j #f #c #jag #j #j ,casing1 bitumen1 and cement #e #c #j #e #e #j #h #j #j ,labour1 ,laying #c #j #j #d #j #j #e #j #j ,trenching and repairing #be #j #jbe #j #jbe #j #j ,surface boxes and connection #e #j #j #g #j #jaj #j #j ,engineer and superintendent #c #j #j #d #j #j #e #j #j ------------------------- ,total #db #aa #jea #h #jgj #j #j ,add extra if copper1 at #i;d4 #j #a #a #j #h #j #a #g #j ------------------------- #db #ab #aea #af #jga #g #j ,cost of copper per lb41 laid complete #e #ac #f #j #ai #d #j #g #i ,current in ampres #ab #ha #bh ,cost per ampre #ce #aj #j #f #h #j #b #aj #f ---------------------------------------- ---------------- ---------------------------------------- -------- #ai_/ab #ai_/aj ---------------------------------------- -------- ,area1 square inches #afac #jbe ,area1 square millimetres #ajd #afabe ,weight per #ajj yards run lb4 #cib #egf ,cost of copper at #g;d4 #ab #ac #j #ah #ae #j ,cost of insulation #bd #ag #j #ce #ag #j ----------------- ,total cost of ,cables #cg #aj #j #ed #ab #j ,casing1 bitumen1 and cement #ab #aj #j #ab #aj #j ,labour1 ,laying #e #j #j #f #j #j ,trenching and repairing #be #j #j #be #j #j ,surface boxes and connection #aj #j #j #aj #j #j ,engineer and superintendent #e #j #j #f #j #j ----------------- ,total #ie #j #jaad #b #j ,add extra if copper1 at #i;d4 #b #ag #j #c #e #j ----------------- #ig #ag #jaag #g #j ,cost of copper per lb41 laid complete #j #e #j #j #d #a ,current in ampres #eh #ij ,cost per ampre #a #ac #i #a #f #j ---------------------------------------- -------- ---------------------------------------- ----------------- #cg_/aj ,two ,sets4 #cg_/aj ---------------------------------------- ----------------- ,area1 square inches #je #aj ,area1 square millimetres #cbb #fde ,weight per #ajj yards run lb4 #aaec #bcjf ,cost of copper at #g;d4 #cg #e #j #gd #aj #j ,cost of insulation #gj #ae #j #ada #aj #j -------------------------- ,total cost of ,cables #ajh #j #j #baf #j #j ,casing1 bitumen1 and cement #af #j #j #bb #j #j ,labour1 ,laying #aj #j #j #ah #j #j ,trenching and repairing #be #j #j #be #j #j ,surface boxes and connection #aj #j #j #aj #j #j ,engineer and superintendent #aj #j #j #aj #j #j -------------------------- ,total #agi #j #j #cja #j #j ,add extra if copper1 at #i;d4 #h #aj #j #ag #j #j -------------------------- #ahg #aj #j #cah #j #j ,cost of copper per lb41 laid complete #j #c #c #j #b #h ,current in ampres #ahj #cfj ,cost per ampre #a #a #j #j #ag #f ---------------------------------------- ----------------- ---------------------------------------- ----------------- ,four ,sets4 ,six ,sets4 #cg_/aj #cg_/aj ---------------------------------------- ----------------- ,area1 square inches #bj #cj ,area1 square millimetres #abij #aice ,weight per #ajj yards run lb4 #dfab #fiah ,cost of copper at #g;d4 #adi #j #j #bbd #j #j ,cost of insulation #bhc #j #j #dbd #j #j -------------------------- ,total cost of ,cables #dcb #j #j #fdh #j #j ,casing1 bitumen1 and cement #dj #j #j #ee #j #j ,labour1 ,laying #ce #j #j #ej #j #j ,trenching and repairing #cj #j #j #ce #j #j ,surface boxes and connection #aj #j #j #aj #j #j ,engineer and superintendent #bj #j #j #be #j #j -------------------------- ,total #efg #j #j #hbc #j #j ,add extra if copper1 at #i;d4 #cd #j #j #ea #j #j -------------------------- #fja #j #j #hgd #j #j ,cost of copper per lb41 laid complete #j #b #g #j #b #f ,current in ampres #gbj #a1jhj ,cost per ampre #j #af #h #j #af #a ---------------------------------------- ----------------- ,,table ,,ii4 ,cost of ,laying #ajj ,yards of ,double ,conductor of ,bare ,copper carried on ,insulators in a ,culvert4 ---------------------------------------- --------------- ,area in square inches #jbe #je #aj ,area in square millimetres #afabe #cbbe #fde ,weight of copper in lb4 per #ajj yards #egf #aaec #bcjf ,cost of copper at #g;d4 per lb4 #ah #ae #j #cg #e #j #gd #aj #j ,laying #i #j #j #i #ab #j #i #ab #j ,insulators #j #d #f #j #d #f #j #d #f #f surface boxes and connections #aj #j #j #aj #j #j #aj #j #j ,culvert1 #ah inches #ab inches1 for two lines conductor1 in brickwork #ec #h #j #ec #h #j #ec #h #j and cement1 replacing pavement ,engineers and superintendence #f #j #j #aj #j #j #aj #j #j ---------------------------- ,total #ig #g #fabj #i #faeg #ad #f ,extra for copper at #i;d4 per lb4 #c #e #j #h #aj #j #ag #j #j ---------------------------- ,total #ajj #ab #fabh #ai #fagd #ad #f ,cost of copper per lb4 laid complete #db;d4 #bg;d4 #ahb;d4 ,current in ampres #ij #ahj #cfj ,cost per ampre #a #b #c #j #ad #e #j #i #h ---------------------------------------- --------------- ---------------------------------------- ------------------ ,area in square inches #bj #bee #cjj ,area in square millimetres #abij #afde #aice ,weight of copper in lb4 per #ajj yards #dfab #fabe #fiah ,cost of copper at #g;d4 per lb4 #adi #j #jaij #j #jbbd #j #j ,laying #i #ae #j #i #ae #j #aj #j #j ,insulators #j #d #f #j #d #f #j #d #f #f surface boxes and connections #aj #j #j #aj #j #j #aj #j #j ,culvert1 #ah inches #ab inches1 for two lines conductor1 in brickwork #ec #h #j #ec #h #j #ec #h #j and cement1 replacing pavement ,engineers and superintendence #aj #j #j #aj #j #j #ae #j #j ------------------------------- ,total #bcb #g #fbfc #g #fcab #ab #f ,extra for copper at #i;d4 per lb4 #cd #j #j #dc #aj #j #ea #j #j ------------------------------- ,total #bff #g #fcjf #g #fcfc #ab #f ,cost of copper per lb4 laid complete #ach;d4 #ab;d4 #ab #f;d4 ,current in ampres #gbj #iaj #ajhj ,cost per ampre #j #g #e #j #f #i #j #f #h ---------------------------------------- ------------------ ,,the ,,vienna ,,central-,,station4 ,the practical success of the ,battery ,transformer system has been demonstrated at ,vienna1 where an installation of five thousand lamps in the ,opera ,house and ,burg ,theatre was maintained for the past year from a distributing station #a1djj yards away4 ,the boilers are fixed in a basement formed by excavating the court-yard of a private house to a depth of #ae feet #f in4 below the street level2 the building itself is utilised partly for offices and partly as a large dynamo and engine-room4 ,each dynamo is designed to give an output of #gb kilowatts or #abj ampres1 at #fjj volts pressure4 ,the current is led by means of a lead-covered cable underground to the accumulators1 which are erected in groups of #eb cells each1 so as to give #ajj volts to the lamps1 with a comfortable margin4 ,the total pressure required to charge the four groups of batteries in series varies from #dcj volts at the time the batteries are giving off work1 to #dhj volts for the short time during which the charge is being completed4 ,during five hours of lighting about two-thirds of the current comes direct from the dynamos2 but during this time1 for short periods1 the demand for current often increases to such an extent that these proportions may be reversed1 and the batteries supply two-thirds of the total4 ,the regulation of groups of batteries placed in series is not a difficult matter1 and will be understood by referring to the following diagram1 ,fig4 #bg3-- ,illustration3 ,,fig4 #bg4 ,the four battery stations mentioned as arranged in series are represented4 ,the current may be supposed to enter at the right hand corner1 passing through the first battery with the lamps parallel to it1 and from that battery to the commencement of the next1 and so on through the third and fourth1 the current being varied at will at the central-station1 or kept constant by means of an electrical governor4 ,the potential for each of the four groups of lamps is maintained in the following manner3--,in each group one terminal is kept permanently connected to one of the discharge mains and to one of the charging mains2 the other terminal can be shifted from cell to cell according to the ,e4 ,m4 ,f4 required in the corresponding lamp circuit by means of a contact regulator4 ,this movable terminal is shown by the bunch of lines at one extremity of each battery group4 ,the rule for charge and discharge is1 that the terminal cell at the regulating end of the battery is so arranged that it neither receives nor gives off current1 so that there is no loss of energy in the shape of ,e4 ,m4 ,f4 ,the contact regulator1 which was designed by ,mr4 ,crompton for use at ,kensington ,court1 is shown by ,fig4 #bh3-- ,illustration3 ,,fig4 #bh4 ,,central-,,station4 ,the ring contacts are arranged in a line in such a manner that a circular contact-piece1 made of thin sheets of copper1 can be forced through them in turn by means of a central screw spindle4 ,the mains for charge and discharge are attached to the fixed disc contacts on the central screws1 and the regulating cells of the battery are coupled to their respective contact rings by sockets at the back of the board4 ,the difficulty with the battery transformer system is the introduction of #djj to #ejj volts into the houses1 which would be necessary without the batteries are always fixed in sub-stations from which a low-pressure current1 say of #ajj volts ,e4 ,m4 ,f41 could only be distributed4 ,a method has been devised by ,mr4 ,henry ,edmunds to obviate this disadvantage4 ,he also uses the high-tension current to charge the batteries1 but by means of a distributor1 which is automatically worked by the current1 each group of cells is charged in turn1 when it is entirely cut off from the supply main to the house1 through which current is perhaps being taken for lighting purposes4 ,the system is now being adopted by the ,cadogan ,electricity ,supply ,company1 ,chelsea4 ,,direct-,,current ,,transformers ,,or ,,dynamotors4 ,the method of transforming by direct current without the aid of batteries is not practically at work2 but1 as the advantages are so obvious and its development is only a question of time1 a description of the system may not be considered out of place4 ,the electrical exhibition at ,philadelphia in #ahhd contained a dynamotor which was exhibited by the ,van de ,poele ,electric-,light ,company1 but1 as far as could be ascertained1 was not worked1 and1 as it was simply described as an induction machine for distributing currents for the use of incandescent and other lights1 it attracted little attention4 ,the advantages of an alternating current transformer system of distribution1 ,class ,,ii41 has been put forward in these pages1 especially that of simplicity and cheapness4 ,an alternating current dynamo for a given output is cheaper than a direct1 and it takes less labour to look after it1 because it has no commutator4 ,an alternating transformer is also an exceedingly simple piece of apparatus4 ,if originally made with due care and kept in a dry place1 it never breaks down1 as it has no moving parts1 and so there is nothing to go wrong4 ,the alternating system of distribution has1 however1 some very serious disadvantages4 ,in the first place1 it is most important that motors should be driven during the day when the lights are not in use4 ,in the second1 batteries cannot be used in an alternating current system1 so any immunity from breakdown that they might ensure is wanting2 and steam must be kept up all day and all night4 ,if motors are wanted during the day1 so that the load on the engine is nearly constant1 batteries are not so valuable1 except with a view of preventing a breakdown2 but1 if batteries cannot be used1 the advantage of using motors becomes enormous1 as the plant has to be large enough to supply the maximum load1 and would otherwise be idle during the day4 ,in alternating current systems there are two difficulties in the way of using motors4 ,it is difficult to make an alternating current motor that will start1 and1 if that difficulty is surmounted1 it is difficult to make an alternating current motor that will work on varying loads without great waste of power4 ,the question of the efficiency of alternating current motors has never been really practically studied yet2 and1 until these difficulties are overcome1 we must regard alternating current motors as non-existent4 ,several methods of working alternating current transformers off direct currents by commutating the primary have been proposed at different times2 but they all seem to be impracticable1 and it seems impossible to get over the difficulties that arise from sparking when it is attempted to break a high-tension circuit4 ,one of the first methods of distribution over large areas proposed was by means of motors and dynamos combined4 ,for instance1 suppose1 in order to keep down the size of the leads1 #b1jjj volts are used in the mains1 a motor capable of working with #b1jjj volts is put down where the lights are wanted1 and this is made to drive a dynamo giving #ajj volts and a large current4 ,instead of having a separate motor and a dynamo connected by a belt or by coupling the spindles together1 it is simpler to make one machine with two armatures1 or to have only one armature with two circuits on it4 ,one circuit is wound with fine wire and takes the #b1jjj volts and tends to turn the armature round4 ,the other circuit is wound with thick wire giving #ajj volts and a large current1 and tends to stop the armature1 thus absorbing the power supplied by the high-pressure circuit4 ,the direct-current transformer or dynamotor is thus a sort of double dynamo1 or dynamo and motor combined4 ,if it gets #b1jjj volts and #aj ampres1 it would1 if there were no waste1 give #ajj volts and #bjj ampres2 with a waste of #aj per cent41 it will give #ajj volts and #ahj ampres4 ,in the ,united ,states it is usual to place an alternating current motor in each house to be lighted2 but the conditions are quite different there1 overhead wires being used extensively4 ,in this country this system is not likely to find favour1 and local sub-stations will be used1 the high pressure1 which is always dangerous to life1 will thus be kept out of private houses and offices4 ,there is1 then1 very little difference in the cost of maintenance of alternating current transformers and dynamotors1 and the advantages possessed by alternating current transformers in this respect are more than counter-balanced by the use of motors on direct current circuits4 ,dynamotors have not come into general use yet because no stations have been started in this country of the size which demands them4 ,no central station with sub-stations is in operation1 but there is every reason to expect several will be soon2 and it is very necessary to discuss the various methods1 not only in use at this moment but coming into use in the immediate future4 ,the dynamotor itself needs no working out1 as any maker of direct-current dynamos can1 of course1 make them4 ,messrs4 ,paris and ,scott of ,norwich showed some in operation at the ,newcastle ,exhibition in #ahhg2 the most successful type is that recently invented by ,mr4 ,jas4 ,swinburne1 illustrated by ,fig4 #bi4 ,the backward main round primary or motor magnet is shown on the left1 and the forward main round the secondary or dynamo magnet on the right1 the outside coil round both magnets is the shunt4 ,illustration3 ,,fig4 #bi4 ,the dynamotor may be made with two circuits on one armature as already explained1 or it may have two armatures in separate fields1 still making up one machine4 ,the first arrangement has two grave disadvantages4 ,there is difficulty about securing perfect insulation between the two circuits1 and this leads to chances of danger in the houses4 ,a dynamotor with two circuits on one armature cannot be compounded1 that is to say1 it cannot be made to give constant electrical pressure on the mains if the number of lamps is varied4 ,a ,swinburne double armature machine can be compounded1 not only to give constant pressure with a varying load1 but to give constant electrical pressure even if both the load and the pressure on the primary circuit vary4 ,this makes a considerable difference in the copper of the primary leads1 as in large and complicated districts it is almost impossible to arrange leads1 even when working with high electrical pressure and small currents1 so that the electrical pressure remains constant1 or even nearly so4 ,a very small variation of the pressure on an incandescent lamp makes an enormous difference in the amount of light it gives1 and in its duration4 ,it is1 therefore1 most important that the ,e4 ,m4 ,f4 on the lamps should be kept absolutely constant4 ,this difficulty is1 of course1 insurmountable in the case of alternating current transformers4 ,alternating current transformers cannot be made to compound1 and the loss in leads cannot be corrected by them1 so that the lamps burn dull at full load4 ,if secondary batteries are used at the sub-stations1 the reduction of pressure might be effected by them4 ,a number would be charged in series and discharged in parallel4 ,this arrangement needs at least two sets of cells1 and cells are expensive2 and it is difficult to preserve the insulation of cells with such electrical pressure as #b1jjj volts4 ,if cells are used for the purpose of equalising the load or as a safety reserve1 it is better to charge them by means of a dynamotor4 ,,installation ,,and ,,working ,,cost ,,of ,,central-,,stations4 ,until the balance-sheet of some large central-station has been published1 it is impossible to do more than surmise what relation the earning power of the generating plant bears to the initial cost4 ,those central-stations which are working successfully in this country at the present time are either too small for a reliable estimate to be formed1 or1 as in the case of the ,grosvenor ,gallery1 the space is too cramped for the large amount of machinery which it has been found necessary to add in order to meet the increasing demands for light4 ,in order to obtain an approximate idea of the cost of installing a station capable of maintaining #aj1jjj lights1 the following data 7,table ,,iii47 given in ,mr4 ,crompton's paper before the ,society of ,telegraph ,engineers are extremely valuable and will be examined with interest4 ,although the figures given are necessarily empirical and open to criticism1 the cost with both systems of distribution is approximately the same1 and may be taken roughly at #e1hfj per #a1jjj lights1 which amount1 according to ,professor ,forbes1 would be reduced to #c1iad per #a1jjj lights if the installation was put down according to ,american practice1 and at the initial cost of the ,westinghouse alternating current system4 ,mr4 ,crompton also compares the working cost of the two systems 7,table ,,iv474 ,,table ,,iii4 ,cost of #aj1jjj-,light1 or #fjj-,kilowatt1#f ,plant4 ,a4,t4--,,alternating ,,transformer ,,distribution4 ,generating station1 buildings1 chimney shaft1 water tanks1 and general fittings #aa1jjj ,dynamos and exciters--#hfe kilowatts1 including spare sets1 divided as convenient #e1edj ,motive power1 i4e41 engines1 boilers1 steam and feed connections1 belts1 c41 at #h #abs4 per ,i4,h4,p4 #ab1dgj #ejj transformers1 i4e41 one to every pair of houses1 at #ae each #g1ejj #b1jjj yards primary or charging main1 exterior to area of supply1 at #cjh per #ajj yards #f1afj #bj1jjj yards distributing main1 #ej mm4 sectional area1 at #ia #gs4 7see ,table ,i47 #ad1bgj ,regulating gear #ejj -------------- #eg1ddj ,b4,t4--,,accumulator ,,transformer ,,distribution4 ,generating station1 buildings1 chimney stack1 water tanks1 and general fittings #h1jjj ,dynamos--#fjj kilowatts1 in six sets of #ajj kilowatts each #d1hjj ,motive power1 i4e41 engines1 boilers1 steam and feed connections1 c41 at #h #abs4 per ,i4,h4,p4 #h1fjj #d groups of accumulators1 in all #bdj cells1 in series1 at #dj per cell1 including stands #i1fjj #b1jjj yards charging main1 at #cjf #ags4 #f;d4 per #ajj yards 7see ,table ,,ii47 #f1acg #bj1jjj yards distributing main1 #afabe mm4 sectional area1 at #ajj #abs4 #f;d4 7see ,table ,,ii47 #bj1abe ,regulating gear #b1ejj -------------- #ei1gfb #f ,kilowatt equals #a1jjj watts4 ,,table ,,iv4 ,working ,expenses and ,maintenance of #aj1jjj-,light1 or #fjj-,kilowatt1 ,plant4 ---------------------------------------- -------------------------- ,direct ,alternating ,transformer ,system4 ---------------------------------------- ------------------------- ,materials-- s4 d4 s4 d4 ,coals3 #d1chj tons at #ags4 #c1gbc #j #j 0 #b1eej 0 #ags4 ,oil1 water1 and petty stores3 #a1ejj hours at #gs4 #f;d4 #g1bej hours at #as4 #ibe #j #j #a1djj hours at #es4 ,total cost of material ----------------- #d1fdh #j #j ,labour-- #b foreman drivers at #des42 #f drivers at #cjs42 #i firemen at #bds42 sundry labour #a1chh #h #j #a foreman driver at #des42 #b drivers at #cjs42 #c firemen at #bds42 sundry labour ,salaries-- #a chief at #ejj2 #b assistants at #bjj each2 #d clerks at #hj each #a1bbj #j #j #a chief at #ejj2 #a assistant at #bjj2 #d clerks at #hj each ----------------- #b1fjh #h #j ,maintenance of ,plant-- ,motive power and dynamos3 #aj per cent4 on #ah1jaj #a1hja #j #j #aj per cent4 on #ac1djj ,buildings and fittings3 #e per cent4 on #aa1jjj #eej #j #j #e per cent4 on #h1jjj ,transformers3 #aj per cent4 on #g1ejj #gej #j #j ,accumulators3 #ae per cent4 on #i1fjj ,mains3 #g per cent4 on #bj1dcj #a1ecb #e #j #b per cent4 on #bf1bfb ,regulating gear3 #aj per cent4 on #ejj #ej #j #j #aj per cent4 on #b1ejj ----------------- #d1fhc #e #j ----------------- #aa1ici #ac #j ----------------- #b1ajj units #cfe days #gff1ejj units4 ,cost per unit #cge;d4 ,continuous ,battery ,transformer ,system4 ---------------------------------------- ------------------------- ,materials-- s4 d4 s4 d4 ,coals3 #d1chj tons at #ags4 0 #b1eej 0 #ags4 #b1afg #j #j ,oil1 water1 and petty stores3 #a1ejj hours at #gs4 #f;d4 #g1bej hours at #as4 #a1djj hours at #es4 #cej #j #j ,total cost of material ----------------- #b1eag #j #j ,labour-- #b foreman drivers at #des42 #f drivers at #cjs42 #i firemen at #bds42 sundry labour #a foreman driver at #des42 #b drivers at #cjs42 #c firemen at #bds42 sundry labour #ige #j #j ,salaries-- #a chief at #ejj2 #b assistants at #bjj each2 #d clerks at #hj each #a chief at #ejj2 #a assistant at #bjj2 #d clerks at #hj each #a1jbj #j #j ----------------- #a1iie #j #j ,maintenance of ,plant-- ,motive power and dynamos3 #aj per cent4 on #ah1jaj #aj per cent4 on #ac1djj #a1cdj #j #j ,buildings and fittings3 #e per cent4 on #aa1jjj #e per cent4 on #h1jjj #djj #j #j ,transformers3 #aj per cent4 on #g1ejj ,accumulators3 #ae per cent4 on #i1fjj #a1ddj #j #j ,mains3 #g per cent4 on #bj1dcj #b per cent4 on #bf1bfb #fef #aj #j ,regulating gear3 #aj per cent4 on #ejj #aj per cent4 on #b1ejj #bej #j #j ----------------- #d1jhf #aj #j ----------------- #h1eih #aj #j ----------------- #b1ajj units #cfe days #gff1ejj units4 ,cost per unit #bg;d4 ---------------------------------------- ------------------------- ,with the exception of the amount allowed for depreciation of the accumulators1 which time alone can show to be correct1 the expenses may be said to be over rather than under-estimated2 the #ae per cent4 depreciation given in ,table ,,iv4 is under what has hitherto been found necessary to allow for the renewal of the plates of a secondary battery4 ,if the mean of the two results in ,table ,,iv4 are taken1 the working cost per ,board of ,trade ,unit will be #cbb;d41 which shows that with both systems1 after making due allowance for interest on capital1 directors' fees1 bad debts1 and other sundries omitted by ,mr4 ,crompton1 there is a probability of a very fair return on the capital expenditure1 and the prospect of a handsome dividend for an electric lighting company who can sell electricity at the average price of #g;d4 per ,unit4 99 99 99 99 99 ,the cost of maintaining and working electric lighting plant at private installations is usually much in excess of a supply from a central-station2 but where the installation is over #ejj lights1 the difference is not very great4 ,the working cost at the ,athenum ,club of #chg lamps for the past year is given as follows3-- s4 d4 ,gas for gas-engine #ddf #g #aj ,oil 0 0 #ga #c #h ,water 0 0 #ce #j #j ,wages #age #b #a ,sundries #cj #c #j ,maintenance of lamps1 etc4 #ih #d #a ,repairs #ajc #a #a ---------- #iei #a #i ---------- ,average cost of lighting by gas and oil for previous years1 for two-thirds number of lights #hdj4 ,at the ,naval and ,military ,club1 #dbj lights cost #hba #ahs4 for the same period1 a steam-engine being used instead of a gas-engine4 ,the annual report of the cost of the electric light at the ,south ,kensington ,museum shows that in a larger installation1 consisting both of arc and incandescent lamps1 the annual cost of the latter is much less than in either of the clubs mentioned4 ,at the ,museum there are #hfj #af candle-power lamps1 working #fee hours per annum1 or #efb1chg lamp hours2 the total cost for working last year was #chf1 which includes #ff for repairs of engines1 boilers1 dynamos1 and maintenance of lamps2 but rent1 interest on capital1 depreciation of plant1 and management is not included4 ,the light is used only three evenings a week1 so that the wages of the attendants are proportionately in excess of what they would be in a central-station4 99 99 99 99 99 ,the cost of arc lighting for street purposes may be estimated from the following tenders4 ,at ,taunton the local electric light company offered to extend the lighting of streets from #bi to #fj arc lamps of #a1bjj candle-power nominal on the ,thomson-,houston system1 at the following rate3-- ,per annum4 s4 d4 ,burning on average of #f hours per night each lamp #ag #g #f #g 0 0 #ah #ab #f #h 0 0 #ai #ag #f ,the posts and supports to be provided and fixed by the company1 or1 if the town council found the same1 the company would allow a deduction at the rate of #e per cent4 per annum upon the outlay made by the council4 ,the lamps are usually about #djj feet apart4 ,the actual cost of operating arc lights on this system is given in the following detailed expenses of a six hours' run of a #ej-light plant for the street lighting of an ,american city3-- #b1fjj lb4 ,ind4 nut and slack coal1 at #acj per ton #afi ,engineer1 one night1 at #ejjj per month #afg ,superintendent or electrician1 one night1 at #ejjj per month #afg ,trimmer1 one day1 at #djjj per month #acc #dh pairs of carbons1 at #ahej per month #hi ,waste1 c41 at #bjjj per year #je ,water rent1 at #djjj per year #aa ,half-pint cylinder oil1 at #fj;c4 per gallon #jd ,one pint engine and dynamo oil1 at #ej;c4 per gallon #jf ,one day repairs on machine and lamps1 including globes1 at #abjjj per year #cc ,one day taxes on #ej-light plant1 assessed at #e1jjj1 at #b per cent4 #ca ,one day interest on #ej-light plant 7#aj1jjj71 at #f per cent4 #afg ---------- ,making a total of #ihb #aj;d4 or #bjde cents4 per lamp4 #ae #ajs4 per annum4 ,if1 in addition to the #ej street lights1 #cc other arc lights are maintained1 the total cost is reduced for a six hours' run to #acbe1 or #b #aes4 #b;d4 for the #hc lights1 #h;d4 or #aeif cents per lamp1 #ab #cs4 #d;d4 per annum4 ,table ,v4 has been calculated by ,m4 ,decker1 of ,nuremburg1 and gives the comparative cost of working #aej lamps by electricity and by gas4 ,the gas price 7#a7 is that paid in ,paris1 namely1 #fs4 #i;d4 per #ajjj cubic feet2 column 7#b7 is the price usually taken commercially1 which includes the fixed charges4 ,the price of electricity is given3 #ast1 when a steam-engine is available2 #bnd1 when it is necessary to lay down a special engine2 #crd1 when a gas-engine is used the gas is charged at a trifle over the price in column 7#a74 ,,table ,v4 ,total ,cost per ,hour and per ,lamp4 ,legend for ,table ,v4 ,a ,number of hours' work per year4 ,b ,number of hours' work per day4 ,c ,steam-engine 7existing74 ,d ,hydraulic ,motor4 ,e ,steam-engine to be erected4 ,f ,gas engine ,g 7#a7 ,gas at #fs4 #i;d4 per #a1jjj ft4 ,h 7#b7 ,gas at #hs4 #i;d4 per #a1jjj ft4 ---------------------------------------- --------------------- ,a ,b ,c ,d ,e ,f ,g ,h ---------------------------------------- --------------------- ,pence4 ,pence4 ,pence4 ,pence4 ,pence4 ,pence4 #ejj #ach #jdhe #ajee #abaf #jdah #jeeb #hjj #bai #jcga #jghj #ajjg #jcii #jeac #a1bjj #cbi #jcad #jfjh #jhfe #jchj #jceb #c1fjj #ihg #jbai #jaeb #jceb #jdhe #jcfa #jdfe ,arc ,lamps4 #ejj #ach #ebce #dbdf #ajdei #aadhe #hjj #bai #ciga #cjhi #geeb #ibgb #a1bjj #cbi #cjhg #bdda #fjjd #geha #c1fjj #ihg #bahe #aeaj #ceia #eehf ---------------------------------------- --------------------- ,,underground ,,or ,,overhead ,,wires4 ,apart from the unsightly appearance of overhead wires1 there are many reasons why any extended system of supply of electricity should be carried out by underground cables4 ,it is true that there have been no accidents in this country due to electric light wires falling1 owing to the care bestowed on their insulation and erection2 on account of the heat generated by the passage of the current through the leads no snow can accumulate on them1 and therefore they are not subjected to the extra weight which destroyed so many of the telegraph and telephone wires in the last snow storm4 ,overhead electric light wires are exclusively used by the largest electric-supply company in ,london1 and it is probable that1 without further legislation takes place1 other companies will shirk the expense of an underground system2 and even a more dangerous method of running cables than that which has been condemned in the principal cities of the ,united ,states will become not the exception but the rule4 ,in the city of ,new ,york the process of conversion of the present overhead to an underground system is a fact about to be accomplished to a very great extent at least1 in the near future4 ,since ,july1 #ahhg1 the ,western ,union ,telegraph ,company have occupied the conduits1 which have been constructed and laid with some #ejj miles of wire2 also the ,metropolitan ,telephone and ,telegraph ,company have #ajjj miles of wire in the subways2 and the ,edison ,illuminating ,company1 whose conductors were laid in the trench at the time of construction1 has more than #ajjj miles of underground cable4 ,the plan adopted is to build conduits of section1 as in ,fig4 #cj1 which shows the subway in course of construction1 with man-hole opening and exposed ends of conduits4 ,the single tube at top is for distribution between man-holes1 and some wires are shown entering the vault on the right from the service box in the foreground4 ,the conduits are of various types2 creosoted wooden tubes are placed in creosoted wooden casings2 wrought-iron pipes are sometimes laid in asphaltic concrete with creosoted wooden box2 another arrangement is to be of composition blocks on concrete1 and cover them with brick--or wrought-iron pipe is lined with cement1 and laid in hydraulic cement concrete and cased with creosoted plank4 ,about #he per cent4 of all the conduits have been constructed on this plan1 the interior diameter of the pipes being #b inches4 ,illustration3 ,,fig4 #cj4 ,illustration3 ,,fig4 #ca4 ,fig4 #ca shows how the street arc lighting wires are taken1 also a branch for house use1 out of the man-holes1 which are placed at each street crossing4 ,for the cleaning purposes and for drawing the cable through the conduits1 these must be laid practically straight4 ,illustration3 ,,fig4 #cb4 ,fig4 #cb illustrates a method proposed by ,mr4 ,kenneth ,mackenzie1 which is somewhat similar to the system of conduit which1 used at ,tours for the past two years1 has been found most efficient for the high potential supply mains to the transformers4 ,the troughs would be about #d ft4 long and #ae in4 deep1 having spigot and socket joints at the ends like ordinary water pipes4 ,transverse pieces of wood1 or preferably slate1 would rest upon projections1 and would support the mains1 and a cover recessed as shown would make the conduit fairly water-tight2 drain holes would be provided1 and the branches to houses led off through glands in the side of troughs4 ,the ,american plan is1 doubtless1 the best1 as there is no space for moisture to collect in the conduits2 but ,mr4 ,mackenzie's system is well worth trying1 and has the advantage of being much cheaper in first cost4 ,the ,edison plan is to place two solid conductors in a tube which is filled up solid with an insulating material1 suitable bends and offsets being supplied1 so that the tube containing the two conductors can be buried in the ground like a gas-pipe4 ,the system is very largely used both in the ,united ,states and in ,continental cities2 but it is doubtful whether the protection would suffice in our towns1 where the streets are already at the mercy of the gas and water companies1 whose workmen1 with a single blow of a pick1 might perforate the tube1 and cause a dangerous short circuit4 ,,the ,,interests ,,of ,,gas ,,companies ,,as ,,to ,,electric ,,lighting4 ,the policy of gas companies with regard to electric light has1 with few exceptions1 been a state of indifference to the progress of things electric1 with contempt for a rival whose opposition is not sufficiently powerful to be appreciated4 ,the chairman of a well-known gas company stated1 what is undisputed1--that the introduction of electric arc lights was accompanied by an increased consumption of gas in the immediate neighbourhood where these lights are used2 but it is very doubtful whether this will be the case when incandescent lights are generally supplied4 ,the introduction of these lights into any business district would mean the displacement of at least as many burners as there are electric lamps2 and this reduction not only means loss of income1 but also loss by interest on plant which is not kept at work to the capacity for which it was designed4 ,the question suggests itself1 8,are existing gas companies more favourably situated for furnishing electricity than any one else80 ,there are many reasons in favour of the supposition that the directors of gas companies have at the present time an opportunity of acquiring almost as complete a monopoly of lighting by electricity as they have with gas4 ,as regards central-stations1 everything is in their favour2 there is generally some spare ground for the machinery1 waste heat could be utilised1 and a cheap fuel in the shape of coke is ready to hand4 ,they have greater facilities for breaking up streets without danger of troubles arising with the local authorities1 and if the ,gasworks ,clauses ,acts1 which authorise their existence1 tie them down to one illuminant1 a very little expenditure would enable them to enlarge their powers4 ,in many towns the shareholders are local men who wish to use the electric light1 but cannot favour its introduction because they think it would tend to smaller dividends or lower quotations for their shares2 if1 however1 a scheme was promoted either by the gas company1 or1 if that was impossible1 if the directors interested themselves in a separate electric light undertaking1 the security which the gas and water investments command would1 no doubt1 cause a sufficient number of local subscribers to come forward and make even a small installation a paying concern4 ,the ,imperial ,continental ,gas ,association have already taken up the supply of electricity in ,vienna1 and are likely to extend this new branch of their business to the other cities in which they hold gas concessions2 also in the ,united ,states the growing opposition of the electric light companies is being seriously discussed1 and already several gas companies are installing electric light plants4 ,it is not at all probable that the scare which caused such a drop in the value of gas shares when the electric light first appeared will be repeated1 but the present high price of gas shares cannot be maintained4 ,kerosene lamps have been for some time a far greater rival to gas than electricity4 ,the cheapening of petroleum1 which is now shipped in bulk to this country in tank steamers1 will cause the consumption to increase1 and enable the oil to be supplied at a price so that it can be used in petroleum-engines1 and give a motive power which will be found to be far more economical than the gas-engine4 ,the latest development of petroleum-engines is that shown by ,messrs4 ,priestman at the ,royal ,agricultural ,society's ,show at ,nottingham4 ,the engine in external appearance is like the ,otto gas-engine1 but uses the ordinary 8paraffin oil0 of commerce1 which has a high flashing point4 ,the oil is simply put into a closed tank1 and on the top of this1 air is forced which drives the petroleum into a chamber heated by the exhaust from the engine1 where it is partially vaporised and led into the cylinder with sufficient air to cause it to ignite by means of an electric spark4 ,the report of the trials with a #e horse-power engine show that a brake horse-power was obtained for #ag lb4 of oil1 or at #f;d4 per gallon for #ad;d4 per horse-power per hour2 with the ,spiel engine the cost is stated to be #jh;d4 per horse-power per hour4 ,any serious reverse to the gas industry would cause a great pecuniary loss to a large number of investors4 ,the paid-up and borrowed capital devoted to the manufacture and supply of gas in the ,united ,kingdom exceeds #ef1jjj1jjj1 of which above #cf1jjj1jjj appertain to the companies and the remainder to the local authorities1 whose receipts in respect of their gas undertakings last year exceeded #d1djj1jjj4 ,the corporation of ,bradford1 who are owners of the gasworks1 have wisely foreseen that it is better to keep the electric light in their own hands1 and are now about to erect a central-station1 and will lay underground wires2 the amount sanctioned for this preliminary installation is #bj1jjj4 ,,the ,,lucigen ,,light4 ,a few remarks on this method of obtaining light from the combustion of crude petroleum may be added1 as the light has been put forward as a cheaper and better substitute for the electric arc4 ,the ,lucigen light is produced by burning creosote oil1 tar oil1 or other heavy hydro-carbons1 by means of compressed air in a special form of lamp1 and consists of a cylinder at the side of which a steam donkey compressing pump is mounted1 or in a more recent form known as the ,wells' light1 no separate air compressor is used1 but1 instead1 the pressure is obtained from the water mains or from a small force pump4 ,the cost is stated to be #c;d4 per hour for #b1ejj candle-power1 requiring three gallons of oil per hour1 but is in reality at the present time double this owing to the price of the oil1 which1 under the most advantageous circumstances1 costs on average #b;d4 per gallon4 ,at the ,forth ,bridge these lights have been found of use in illuminating open spaces1 but have not supplanted the electric arc lights which are universally employed for the lighting of the works and the interior of the shops4 ,the disadvantages are the noise1 the oil shower which pervades the vicinity of the light causing timber staging to be highly inflammable1 and the difficulty of preventing water from entering the burner1 a few drops sufficing to extinguish the light4 ,the use of the ,lucigen light is1 therefore1 very limited1 and it is probable that1 in situations where shadows from the arc light are found to be objectionable1 large incandescent electric lamps1 which are supplied up to #a1ejj candle-power1 would meet the case2 or1 failing these1 petroleum could be burnt in lamps similar to those used in lighthouses with greater safety1 and at not much increased cost1 than the compressed-air system4 ,,useful ,,notes4 ,to ascertain in what direction the electric current is flowing through any wire by means of a pocket compass3-- ,a current flowing from south to north will always deflect the needle to the west1 providing the wire in which the current flows is over the instrument4 ,the word ,s4 ,n4 ,o4 ,w4 expresses this--south north over west2 and should be remembered4 ,another simple plan is to hold the outstretched right hand over the compass2 then1 if the current flows in the direction of the wrist to the fingers1 the needle will move towards the thumb4 ,to find the direction of the current in the wire of an electro-magnet3 ,place the palm of the hand on the coil with the fingers parallel to the wires3 the thumb will point to the ,north ,pole if the current is flowing as in previous rule towards the fingers4 ,conversely3 if the ,north ,pole is known1 the fingers will point to the direction of the current when placed parallel with the wires1 with the thumb pointing to the ,north ,pole4 ,if no compass is available1 take two pieces of lead and place a few inches apart in a pot containing dilute sulphuric acid1 scrape the lead clean1 and join a piece of wire to each and connect to poles to be tested4 ,after current has passed a short time one piece of lead will become brown1 the other grey2 trace the former to the dynamo cable1 and this is the positive1 and should be marked with a or be painted red for future distinction4 ,incandescent ,lights or ,glow ,lights4 ,the number of lights required to illuminate any room would vary very much1 according to the style of decoration and position of the lamps4 ,as a rule1 a similar number of glow lamps are required as there would be gas burners4 ,the former give a much higher standard of illumination1 which1 curiously enough1 is generally expected with electric lighting on account of the purity of the atmosphere when the full light is being used1 which is not the case with gas4 ,one #af candle-power lamp will light an area of about #h feet in diameter at #h feet above ground2 in ordinary situations allow1 one lamp for #ch square feet4 ,arc ,lighting of ,works4 ,external4--#ef4 #b1jjj ,,cp4 arc lights will illuminate #afj1jjj square yards1 or one for each #b1hjj square yards4 ,internal4--#dc4 #b1jjj ,,cp4 arc lights will illuminate #ca1ejj square yards1 or one for each #gcj square yards4 ,approximate ,cost of ,electric ,light1 ,museum4 ,arc lighting1 #b_/e gas2 with interest1 4 ,incandescent1 gas2 with interest1 #d_/c4 ,motive ,power4 ,compound engine #b lbs4 of coal per indicated horse-power per hour4 ,good single-acting engine #c to #f per indicated horse-power per hour4 ,an indicated horse-power can be obtained in a compound engine from #bj lbs4 of steam per hour4 ,a good boiler evaporates #i to #aj lbs4 of water per lb4 of coal4 ,from #ba to #bh cubic feet of gas are required in a gas-engine per indicated horse-power per hour4 ,incandescent ,lamps4 ,in practice allow #i-fj watt #af ,,cp4 lamps per indicated horse-power of engine4 ,mem4 for ,wire ,running4 ,leads to the left or 8low10 8light coloured40 ,returns to the right or 8raised10 8red40 ,english and ,french ,measures4 ,millimetre #jjci inches #a mill #jbed millimetres4 ,centimetre #jcic 0 #a inch #becii centimetres4 ,decimetre #cic 0 #a foot #ccdhj decimetres4 ,metre #cicg 0 #a yard #iadci metres4 ,cubic metre #cecb cubic feet or #aca cubic yards4 ,,electrical ,,measurements4 ,the ,paris ,congress ,units 7#ahhd7 are now universally adopted and consist as follows3 ,electro-motive ,force1 and ,potential 7,e74--,the ,volt4 ,the legal volt is #ibf of the ,e4 ,m4 ,f4 of a ,daniell's cell1 which for rough purposes may be taken as a volt4 ,resistance 7,r74--,the ,ohm4 ,the legal ohm is now represented by the resistance of a column of mercury of a square millimetre in section at the temperature of zero centigrade #ajfb metres long4 ,current 7,c74--,the ,ampre4 ,this is the strength of current sent through a wire having the resistance of #a ohm at the ,e4 ,m4 ,f4 of #a volt4 ,quantity 7,q74--,the ,coulomb4 ,it is the quantity of electricity given by an ampre in a second4 ,one coulomb decomposes #jjadb grain of water4 ,heat or ,work 7,w74--,the ,joule1 or ,volt-,coulomb1 is the work done by #a coulomb in #a ohm4 ,the work done by any current per second is obtained in ergs by the product of the current into the electro-motive force producing it or ,w ,,ce or ,w ,c,r4 ,the ,erg is the ,c4 ,g4 ,s4 unit of work4 ,power 7,p74--,the ,watt1 #a #gdf of a horse-power1 employed in doing #a joule of work in #a second4 ,,hp1 or the ,horse-power1 is found by dividing ,c ,e by #gdf1 thus 7,,ce7_/#gdf or 7,c,r7_/#gdf ,,hp4 ,see also explanation of terms4 ,,electrical ,,table ,,of ,,the ,,birmingham ,,wire ,,gauge ,,for ,,pure ,,copper4 ---------------------------------------- -------------------- ,b4 ,diam4,diam4,area in,circum4 ,pounds ,feet ,feet ,ohms ,w4 in in ,square in per per per per ,g4 ,in4 mm4 ,inches4,inches4 ,mile4 ,pound4 ,ohm4 #ajjj ,no4 ,feet4 ---------------------------------------- -------------------- #a #c #gfb #jgjfhfidbdh #adddjjhg #cffb #hgjfhdc #aadh #b #bhd #gba #jfccdghibba #abiahfii #djihhghjcea #abhb #c #bei #feh #jebfhehacfg #ajgdefig #dibfbfdijji #aedj #d #bch #fjd #jdddhhgdggj #ijgcfhc #ehej #eehjja #agjjg #e #bb #eei #jchjacfiaae #ggcjde #fhc #dfhaa #bacf #f #bjc #eaf #jcbcfefcggd #fegbje #hjb #ciheg #beji #g #ahj #deg #jbeddgefedi #eagdic #ajbj #cacdh #caij #h #afe #dai #jbachbeahcf #dcdhfa #abad #bfccg #cgig #i #adh #cgf #jagbjcdfdie #cdihec #aeaj #baaii #dgai #aj #acd #cdj #jadajcdbjig #bhffea #ahdd #agcgj #egeg #aa #abj #cje #jaacjicgfii #bbiiig #bbie #acibi #gagi #ab #aji #bgg #jjiccacdbdc #ahigfc #bghb #aadid #hgjj #ac #jie #bda #jjgjhhbihde #addadd #cffc #hgca #aaded #ad #jhc #baa #jjedaabfjge #aajjce #dgih #ffec #aejc #ae #jgb #ahc #jjdjgabbfai #hbgij #fcgg #ejae #aiida #af #jfe #afe #jjccahbjdbj #fgdgh #ghbe #djhg #bddff #ag #jeh #adg #jjbfdbahbba #eacafcajbhi #cajh #cbagf #ah #jdi #abd #jjahhfaecid #chcdhfacgfh #bcbc #dcjeb #ai #jdb #ajg #jjacheacaie #bhagdaahgdj #agjf #eheii #bj #jce #hi #jjjifbajiie #aiefggbfihc #aahe #hdcha #ba #jcb #ha #jjjhjdajjec #afcegdcbbgi #iia #ajjid #bb #jbh #ga #jjjfafjhgif #abebdbdbaeh #geh #acahe #bc #jbe #fc #jjjdiajghed #iihdeebhhb #fje #afeci #bd #jbb #ee #jjjchjjfiaa #ggbiifhcjf #dfh #baceg ---------------------------------------- -------------------- ,,electrical ,,resistance ,,of ,,copper ,,wire ,,in ,,french ,,measurements4 ---------------------------------------- -------------------- ,b4,w4,g4 ,diameter ,area ,circumference ,metres ,kg4 ,no4 in in in per per ,millimeters4 mm4 ,millimeters4 ,kilogramme4 ,metre4 ---------------------------------------- -------------------- #a #g4fb #de4f #bc4i #a4ie #j4ead #b #g4ba #dj4h #bb4f #b4gh #j4cfj #c #f4eh #cd #bj4g #c4cc #j4cjj #d #f4jd #bh4g #ai #c4ie #j4bec #e #e4ei #bd4e #ag4f #d4fa #j4bag #f #e4af #ba #af4b #e4dc #j4ahd #g #d4eg #af4d #ad4c #f4ij #j4ade #h #d4ai #ac4h #ac4a #h4bj #j4abb #i #c4gf #aa4a #aa4h #aj4bj #j4jih #aj #c4dj #i4a #aj4g #ab4ej #j4jhj #aa #c4je #g4c #i4f #ac4ej #j4jgd #ab #b4gg #f #h4g #ah4hg #j4jec #ac #b4da #d4f #g4f #bd4hj #j4jdjc #ad #b4aa #c4e #f4fc #cb4dj #j4jcji #ae #a4hc #b4fc #e4ge #de4aj #j4jbcb #af #a4fe #b4ad #e4ah #eb4ij #j4jahi #ag #a4dg #a4gj #d4fb #fi4dj #j4jadd #ah #a4bd #a4ba #c4ij #id4cj #j4jajf #ai #a4jg #j4i #c4cf #ace4aj #j4jjgd #bj #j4hi #j4fb #b4hj #aha4h #j4jjee #ba #j4ha #j4ea #b4ed #bab4h #j4jjdg #bb #j4ga #j4ci #b4bc #bhe4g #j4jjce #bc #j4fc #j4ca #a4ih #cfd #j4jjbh #bd #j4ee #j4bd #a4gc #dfe #j4jjbae ---------------------------------------- -------------------- ---------------------------------------- ----------------- ,b4,w4,g4 ,resistance in ,ohms ,kilogrammes ,metres ,no4 ----------------------------- per per per ,kilogramme4 per ,metre4 ,ohm4 ,ohm4 ---------------------------------------- ---------------- #a #j4jjjgceae #j4jjjcgg #acfj #bfeb #b #j4jjaafgfj #j4jjjdbj #hfj #bcgi #c #j4jjafhafe #j4jjjeje #eie #aihj #d #j4jjbcbbfj #j4jjjehh #dcj #agjj #e #j4jjcbbgjj #j4jjjgjj #caj #adcj #f #j4jjdebcai #j4jjjhcc #bbj #abjj #g #j4jjgcadjj #j4jjajf #acg #ide #h #j4jajbejjj #j4jjabe #ih #hjb #i #j4jaehajjj #j4jjaee #fc #fdf #aj #j4jbcgejj #j4jjaij #db4bj #ebg #aa #j4jcahfjj #j4jjbcf #ca4dj #dbd #ab #j4jecifhb #j4jjbhf #ah4fj #cej #ac #j4jicbdhj #j4jjcgf #aj4gj #bff #ad #j4afjchj #j4jjdie #f4bf #bjb #ae #j4bidied #j4jjfed #c4dj #aec #af #j4dcjjgg #j4jjhac #b4cj #abc #ag #j4gcefd #j4jajf #a4ce #id4e #ah #a4ccijf #j4jadb #j4ge #gj4d #ai #b4fjgdc #j4jaic #j4ch #ea4i #bj #e4jedjd #j4jbgh #j4bj #cf #ba #g4jdcfh #j4jcca #j4ad #cj4b #bb #ab4cgjha #j4jdcc #j4jh #bc4a #bc #ai4fibd #j4jeda #j4je #ah4e #bd #cb4eejj #j4jgjj #j4jc #ad4c ---------------------------------------- ---------------- ,for ,table of ,english ,measurements see page #aje4 ,,explanation ,,of ,,terms4 ,accumulator4--,another name for secondary batteries4 ,alternate ,current ,dynamo4--,produces currents which are alternately positive and negative4 ,amalgamation4--,zinc is protected from local action by having its surface coated with mercury4 ,ampre4--,the ,unit of current4 ,a volt divided by an ohm4 7,see ,electrical ,measurements1 page #ajd47 ,ampre ,meter4--,an instrument used for measuring strength of current4 ,anode4--,the positive electrode or pole of a decomposing cell1 the wire or plate connected to the copper or other negative element of a battery4 ,in electro-plating1 it is usually the soluble pole of the metal to be deposited4 7v4 ,cathode47 ,arc4--,the air space in which the electric light forms4 ,armature4--,the keeper of a magnet3 the part which closes the magnetic lines of the field-magnet1 or the rotary part4 ,battery4--,a combination of two or more voltaic cells coupled together4 ,b4 ,a4--,british ,association4 ,block ,station4--,a central-station for the supply of continuous buildings4 ,board of ,trade ,unit4--,one thousand watt hours equals #aj ampres at #ajj volts per hour1 or #ace ,,hp4 working for one hour4 ,bobbin4--,a coil of wire1 or a number of such coils1 generally so mounted that they can be rapidly revolved4 ,bridge 7,wheatstone's74--,an apparatus for measuring resistances by balancing the unknown resistance against one known and capable of adjustment4 ,b4 ,w4 ,g4--,birmingham wire gauge4 ,candle-,power4--,term used to denote the amount of light as compared with a standard sperm candle1 which is a spermaceti candle1 burning at the rate of #b grains per minute4 ,carbons4--,the electrodes of arc lamps2 the negative plate of a battery4 ,carcel ,lamp4--,the ,french standard1 equal to #id candles4 ,capacity 7,k74--,the powder of a surface to hold electricity as 8static charge40 ,a coulomb divided by a volt4 ,its ,unit is the ,farad4 ,cathode4--,the negative pole of a battery2 the wire or plate connected with the zinc or positive element of the battery4 ,the object on which a metallic deposit is to be formed4 7v4 ,anode74 ,centimetre4--,the hundredth part of a metre4 ,cell4--,each separate vessel in which a chemical action occurs1 by which electricity is capable of being developed4 ,central-station4--,a building containing plant for supplying electricity to the public4 ,c4 ,g4 ,s4--,the centimetre-gramme-second system4 ,circuit ,conductive4--,the wires which form the path for the passage of the current4 ,commutator4--,a circuit changer1 or switch4 ,the collector of currents on a dynamo4 ,compound ,winding4--,a method of increasing or decreasing the energy developed in a dynamo in proportion to the demand4 ,conductivity4--,is the reciprocal to resistance1 and applies to that property of any substance whereby the passage of electricity through it is effected with the least opposition4 ,conductors4--,substances which most freely permit electricity to pass4 ,connections4--,wires1 c41 completing the circuit between different apparatus4 ,contact ,breaker4--,the electric lighting equivalent for a gas tap4 ,coulomb 7,q74--,the ,unit of quantity1 which passes in one second of an ampre current4 ,cut-out4--,an instrument placed in the circuit which will open it automatically4 ,current 7,c74--,the ,unit is the ,ampre4 ,the supposed flow or passage of electricity or electrical force in the direction from to -1 or positive to negative4 ,current ,reverse4--,a current in the opposite direction to the normal current4 ,decimetre4--,the tenth part of a metre4 ,deflection4--,the angle or number of degrees through which the needle of a galvanometer moves when a current is passing through its coils4 ,diaphragm4--,a porous division between two liquids through which electric current passes4 ,duplex ,cut-out4--,an instrument which enables a spare fuse to be immediately substituted for that melted4 ,duty4--,a term used to denote the economy of any motor4 ,dynamo4--,a name given to machines which produce electricity for commercial purposes4 ,dynamometer4--,an instrument for ascertaining the horse-power absorbed by any machine4 ,dyne4--,the ,unit of force which gives a velocity of #a centimetre per second to #a gramme weight after acting for #a second4 ,direct-,current ,dynamo4--,an electric generator producing currents passing in one direction4 ,earth4--,a term for the return circuit1 which for economy is formed through the earth in telegraph work4 ,a return conductor common to many circuits is sometimes called 8earth40 ,electrodes4--,a term for the poles or plates leading the current into and out of a cell4 ,electrolysis4--,the act of decomposition by the electric current4 ,electrolyte4--,the liquid in a cell4 ,electrometer4--,an instrument for measuring electric potential4 ,electro-motive ,force 7,e4 ,m4 ,f47 7,e74--,the electric force tending to produce electric current4 ,the ,unit is the volt4 ,erg4--,the ,c4 ,g4 ,s4 ,unit of energy4 ,the work of moving a body through #a centimetre against the force of a dyne4 ,extra ,current4--,the induced current of higher ,e4 ,m4 ,f41 which appears in a wire wound in a helix when the current is broken4 ,farad4--,the ,unit of capacity3 a coulomb divided by a volt4 ,field of ,force4--,the space between or around the poles of a magnet4 ,filament4--,that part of an incandescent lamp which gives out the light4 ,field-,magnets4--,in a dynamo the magnets between which the armature revolves4 ,foot ,pound4--,the ,british ,unit of work1 or #a lb4 raised #a foot high4 ,galvanometer4--,an instrument for measuring current4 ,generator4--,another term for a dynamo4 ,governor4--,an apparatus for controlling the speed of any motor4 ,horse-,power 7,,hp47--indicated ,,hp4--,the ,unit is #cc1jjj lbs4 lifted #a foot high per minute4 ,the nominal ,,hp4 of any motor is generally fixed considerably less than the indicated4 #b7;,a ,p ,r ,s7 ,ind4 ,,hp4 of any engine ------------------ #cc1jjj ,a ,area of piston in square inches4 ,p ,average pressure of steam in lbs4 per square inch4 ,r ,number of revolutions per minute4 ,s ,length of stroke in feet 7if in inches1 #cc1jjj by #ab74 ,the ,french 8force cheval0 represents #cb1efj foot pounds4 ,horse-,power of ,water4--,indian ,government rule1 #ae cube feet per second falling through #a foot #a ,,hp4 ,indicator ,diagram4--,the drawing produced by an instrument which is fixed to the cylinder of a steam-engine for the purpose of ascertaining its duty4 ,induction4--,the name given to effects produced out of a force-exerting body or out of the circuit to which the force is directly applied4 ,a current in a wire induces currents in other conductors parallel to it4 ,inertia4--,the resistance to change of state of rest or motion4 ,insulators4--,bodies possessing high electrical resistance4 ,all insulating substances1 however1 allow some electricity to pass4 ,intensity4--,the old term for the properties now described as ,e4 ,m4 ,f4 and potential4 ,joule1 also called ,joulad 7,w74--,the ,unit of heat or work1 it has also been applied to the mechanical equivalent of heat1 #ggb foot lbs4 ,kilowatt4--,one thousand watts4 ,knot4--,the geographical and nautical mile4 ,leads4--,terms usually applied to copper conductors4 ,magnetism4--,a condition which can be highly developed in iron and steel1 by electric action or otherwise4 ,measurement4--,see ,units4 ,metre4--,the ,french standard of length #cbh feet4 ,meg ,ohm4--,the prefix meg signifies a million4 ,millimetre4--,the thousandth part of a metre4 ,milliampre4--,the thousandth of an ampre4 ,mica-foil4--,the fusible portion of a ,hedges cut-out4 ,multiple ,arc4--,galvanic cells or dynamos connected parallel1 or lamps so arranged that each furnishes a separate path for the current4 ,negative4--,in a machine the wire returning from the lamp4 ,in a galvanic battery the copper1 carbon1 or platinum plate4 ,sign -4 ,nigger4--,an ,american term used to denote an electrical fault4 ,ohm4--,the ,unit of resistance4 ,a volt divided by an ampre4 ,ohm's ,laws4--,laws1 investigated by ,ohm1 regulating electrical current magnitudes4 ,calling the current ,c1 electro-motive force ,e1 and resistance ,r3 the expression is ,current ,e4 ,m4 ,f4 ,resistance4 ,e ,e ,c ----1 amps4 ,e ,c ,r1 volts4 ,r ---- ohms4 ,r ,c 7,see ,electrical ,measurements47 ,osmose4--,the process of diffusion of liquids through a porous division4 ,paraffin4--,an insulating substance much used in telegraphic work4 ,plummer ,block4--,the bearing on which a shaft revolves4 ,polarity4--,the distinct features of the two separate poles of a magnet4 ,poles4--,the two ends of a magnet4 ,the wires1 plates1 c41 leading from a battery4 ,positive4--,in a machine the wire proceeding to the lamp4 ,in a battery the zinc plate4 ,sign 4 ,potential4--,a word used to indicate a condition for work4 ,difference of potential is a difference of electrical condition4 ,potential of a battery means its ,e4 ,m4 ,f4 ,power 7,p74--,the rate of doing work4 ,when an ampre passes through an ohm1 the unit power1 called a watt1 is required4 ,quantity 7,q74--,the ,unit is the ,coulomb4 ,relay4--,an electro-magnet which1 receiving its current from a distance1 closes the circuit of a local battery so as to produce the required effect of strength4 ,resistance 7,r74--,the opposition presented by the circuit to the development of the current4 ,the ,unit of resistance is the ,ohm4 ,rheostat4--,an instrument for inserting resistances4 ,a valuable artificial resistance employed for measuring unknown resistances4 ,return ,current4--,the current in the wire leading to the machine4 ,rigger4--,the pulley or wheel by which power is transmitted4 ,secondary ,battery4--,wrongly termed an accumulator1 is an appliance for storing energy in such a form that it shall be available for the reproduction of electric currents4 ,secondary ,generator4--,a transformer of a current of high potential into a current of less ,e4 ,m4 ,f4 ,series4--,the plan of connecting lamps so that the current passes one after the other4 ,shunt4--,a coil of wire arranged to take a certain proportion of any current4 ,solenoids4--,helices of wire which act like magnets4 ,switch4--,an apparatus for changing one circuit on to another4 ,spectrum4--,the elongated figure of the prismatic colours4 ,torque4--,term used to express the strain on a shaft due to electro-magnetic action4 ,units4--,the various bases of any system of measurement4 ,volt4--,the ,unit of electro-motive force and potential4 ,an ampre multiplied by an ohm4 7,see ,electrical ,measurements47 ,voltameter4--,an apparatus for measuring the current by its chemical action4 ,voltmeter4--,an instrument used for measuring ,e4 ,m4 ,f4 ,watt4--,the ,unit of power4 ,a volt-ampre4 ,the horse-power electrical1 taken as #gdf ,b ,a watts1 is equivalent to only #gcf true watts4 ,the horse-power electrical is equal to #gef ,b ,a watts1 which is equal to #gdf true watts4 ,the 8force de cheval10 or horse-power in use abroad1 is defined as #ge kilogrammetres1 and is1 therefore1 #gcf true watts4 ,work 7,w47--,is a volt multiplied by a coulomb1 or 7amp4 sec ohm7 or 7amp4 sec volt74 ,the ,unit is the ,joule4 ,yoke4--,is a term applied to the apparently neutral mass of iron which connects the poles of a horse-shoe magnet at the back4 ,illustration ,,appendix ,i4--,,principal ,,electric ,,lighting ,,stations ,,in ,,great ,,britain4 ---------------------------------------- -------------------- ,approximate ,approximate ,no4 of ,lights4 length of ,name of ------------- ,systems longest ,main ,station4 ,incan- employed4 main conductor descent ,arc4 supply overhead or or ,glow conductor underground ,lamps4 in miles4 ---------------------------------------- ------------------- ,brighton ,high-tension ,electric- #a1hjj #dj lamps in #bj ,overhead ,light multiple ,company series ,brush ,dynamos ---------------------------------------- ------------------- ,cadogan ,electricity ,edmunds' ,supply system #b ,overhead ,company of ,battery 7,new ,transformers ,company7 ---------------------------------------- ------------------- ,lowrie ,hall #g miles ,eastbourne #a1gjj #cj ,transformers #ae under- ground ---------------------------------------- ------------------- ,high-tension ,grosvenor with ,ferranti #f ,district ,transformers circuits1 ,electrical #bj1jjj #dj primary total ,supply #b1djj volts1 about ,overhead secondary #gj miles #bjj volts1 ,ferranti dynamos ---------------------------------------- ------------------- ,kensington ,crompton ,court #afjj #aje volts ,electric to be low-tension1 ,underground ,lighting extended constant ,company to supply #aj1jjj by means of accumulators ---------------------------------------- ------------------- ,low-tension ,overhead ,liverpool #a1jjj continuous and current ,underground dynamos ---------------------------------------- ------------------- ,chamberlain ,leamington #a1ejj and ,hookham ,underground dynamos with #a accumulators ---------------------------------------- ------------------- ,paddington #d1aae #ih ,e4 ,m4 ,f4 ,electric #af ,c4 ,p4#c1jjj #aej volts1 ,lighting lamps ,c4 ,p4 ,gordon #c ,underground alternating current ,dynamos ---------------------------------------- ------------------- ---------------------------------------- ------------- ,charges4 ,name of ,approximate ,station4 area of ,working ,hours of------------ distribution4,capital4,supply4 ,by ,meter4 ---------------------------------------- ------------- ,brighton ,meter ,electric- ,about #c rent1 ,light square #ab1jjj;,constant#bas4 #h;d4 ,company miles per annum ---------------------------------------- ------------- ,cadogan ,electricity,belgravia and ,supply ,cadogan ,company ,estate #bj1jjj 7,new ,company7 ---------------------------------------- ------------- ,eastbourne #bj1jjj;,constant ---------------------------------------- ------------- ,very irregular ,grosvenor district1 #g per ,district a house is #cge1jjj #h ,a4,m4 ,board of ,electrical lighted to ,trade ,supply #b miles #c ,a4,m4 unit station from the station ---------------------------------------- ------------- ,the streets ,kensington adjoining ,by meter ,court the station1 and minimum ,electric the mains to #be1jjj;,constant charge of ,lighting be continued #ajs4 per ,company to another light per station at annum ,knightsbridge ---------------------------------------- ------------- ,liverpool ,by meter #bj1jjj on sliding scale ---------------------------------------- ------------- ,leamington #ahc street ,constant lamps meter ---------------------------------------- ------------- ,paddington ,electric ,lighting #fg acres ,constant ---------------------------------------- ------------- ---------------------------------------- ------------------------- ,charges4 ,name of ,station4 --------------------------------- ,remarks4 ,by yearly fixed amount4 ---------------------------------------- ------------------------- ,brighton ,glow lamps1 #as4 per unit1 or ,if consumption ,electric- rather over d4 per lamp is below ,light per hour4 ,arc lamps1 #ds4 per #ajj units ,company lamp per week including quarterly1 maintenance #aj;d4 discount4 ---------------------------------------- ------------------------- ,cadogan ,electricity ,supply ,company 7,new ,company7 ---------------------------------------- ------------------------- ,according to consumption ,a similar ,eastbourne averaging about #f;d4 station per unit at ,hastings4 ---------------------------------------- ------------------------- ,grosvenor ,district ,a station at ,electrical ,deptford is ,supply under erection to maintain #bjj1jjj lights4 ---------------------------------------- ------------------------- ,kensington #h;d4 per unit1 equal to #jef;d4 ,court per #bj ,c4-,p4 lamp per hour1 ,district embraces ,electric or #jbh;d4 per #aj ,c4-,p4 lamp4 residences1 shops1 ,lighting ,shops taken at #b per annum public hall1 and ,company per #bj ,c4-,p4 lamp minimum church4 of #aj lights ---------------------------------------- ------------------------- ,board of ,trade ,liverpool ,first #djj hours1 #as4 per unit license for six ,second 0 0 #h;d4 0 years1 hotels1 shops1 ,afterwards #d;d4 0 and residences4 ---------------------------------------- ------------------------- ,street lights #b #bs4 per annum for #b1hfj hours1 including renewals4 ,leamington #a to #dj units per quarter #h;d4 per unit4 #da to #aej units per quarter1 #f;d4 per unit4 #aea units per quarter #d;d4 per unit ---------------------------------------- ------------------------- ,paddington ,the district between ,electric ,paddington and ,lighting ,worked by ,g4 ,w4 ,railway ,westbourne ,park is lighted throughout4 ---------------------------------------- ------------------------- ---------------------------------------- ------------------ ,approximate ,approximate ,number of ,lights4 length of ---------------- longest ,name of ,incan- ,system employed4 main ,station4 descent ,arc4 supply or ,glow conductor ,lamps4 in miles4 ---------------------------------------- ----------------- ,barnet and ,district #e ,e4 ,supply ,joel ,dynamos ,company 7,new ,company7 ---------------------------------------- ----------------- ,chelsea ,e4 ,supply ,company 7,new ,company7 ---------------------------------------- ----------------- ,st4 ,james and ,pall ,continuous ,mall current 7,new ,company7 ---------------------------------------- ----------------- ,thompson ,houston ,taunton4 #bc continuous current ---------------------------------------- ----------------- ,whitehall ,battery ,court ,transformer 7,new ,company7 system ---------------------------------------- ----------------- ,westminster ---------------------------------------- ----------------- ,west ,lowrie ,hall #aj miles ,brompton ,transformers when completed ---------------------------------------- ----------------- ,adelphi ,continuous #ab ,theatre #d1jjj current external dynamos circuits coupled direct to engines ---------------------------------------- ----------------- ,bath ,thomson 7,new ,company7 #he ,houston ,dynamos and ,transformers ---------------------------------------- ----------------- ---------------------------------------- ---------------- ,main conductor overhead ,approximate area ,working ,hours of ,name of or under-of distribution4 ,capital4 ,supply4 ,station4 ground4 ---------------------------------------- ---------------- ,barnet and ,overhead ,district chiefly #e1jjj ,e4 ,supply ,company 7,new ,company7 ---------------------------------------- ---------------- ,chelsea ,e4 ,supply ,company 7,new ,company7 ---------------------------------------- ---------------- ,st4 ,james and ,pall #bj1jjj ,mall 7,new ,company7 ---------------------------------------- ---------------- ,taunton4 ,overhead ,street lighting ---------------------------------------- ---------------- ,whitehall ,to light ,court hotels in #bd1gec;,constant 7,new ,company7 ,northumberland ,avenue ---------------------------------------- ---------------- ,westminster ---------------------------------------- ---------------- ,west ,brompton ,constant ---------------------------------------- ---------------- ,adelphi ,over- ,the buildings ,theatre head are close ,private and together under- ground ---------------------------------------- ---------------- ,bath 7,new ,company7 ,arc lights in streets ---------------------------------------- ---------------- ---------------------------------------- ------------------------- ,charges4 ,name of --------------------------------- ,station4 ,by ,meter4 ,by yearly ,remarks4 fixed amount4 ---------------------------------------- ------------------------ ,barnet and #ga lamps in ,district streets on posts ,e4 ,supply #ab ft4 high4 ,company 7,new ,company7 ---------------------------------------- ------------------------ ,chelsea ,e4 ,supply ,company 7,new ,company7 ---------------------------------------- ------------------------ ,st4 ,james ,area to be and ,pall lighted ,mall adjoining 7,new station4 ,company7 ---------------------------------------- ------------------------ ,taunton4 ,by yearly contract ,arc lamps of #abjj-;,c4-,p4 ---------------------------------------- ------------------------ ,whitehall ,proposed ,proposed charge1 ,amalgamated ,court meter- #h;d4 per unit with with the 7,new rent minimum of #a4 #a ,metropolitan ,company7 #ajs4 per per lamp per annum ,electric quarter ,supply ,company4 ---------------------------------------- ------------------------ ,westminster ,new ,company4 ---------------------------------------- ------------------------ ,west ,by meter ,the station is being erected by the ,house ,brompton to ,house ,lighting ,company1 who also propose installations in other districts4 ---------------------------------------- ------------------------- ,adelphi ,the ,adelphi ,theatre1 ,adelaide ,gallery1 ,theatre and ,strand ,restaurant are lit1 the machinery being fixed in a basement about #cj #de feet4 ,no gas is laid on4 ---------------------------------------- ------------------------ ,bath ,the power obtained 7,new ,yearly contract from town weir ,company7 supplemented by steam-engine4 ---------------------------------------- ------------------------ ,,appendix ,,ii4--,,principal ,,electric ,,lighting ,,stations ,,on ,,the ,,continent4 ---------------------------------------- ---------------------- ,approximate ,approximate ,number of ,lights4 length of -------------------- longest ,name of ,incan- ,system main ,station4 descent ,arc4 employed4 supply or ,glow conductor ,lamps4 in miles4 ---------------------------------------- --------------------- ,bergen #c1jjj #gj ,brush ---------------------------------------- --------------------- ,bellegarde #fjj ,gramme dynamos ---------------------------------------- --------------------- ,berlin #aa1hjj ,edison lamps #ajj volts 0 #ag1djj 0 #a 0 #c1jjj #ajh 0 0 #db1bjj #djj 0 ---------------------------------------- --------------------- ,breslau #e1jjj #fi ,siemens ---------------------------------------- --------------------- ,brunswick #b1jjj ,edison ---------------------------------------- --------------------- ,crefeld #a1efj 0 ---------------------------------------- --------------------- ,darmstadt #a1jjj 0 ---------------------------------------- --------------------- ,dresden #c1djj 0 ---------------------------------------- --------------------- ,elberfeld #b1jjj 0 ---------------------------------------- --------------------- ,hamburg #d1jjj #ej ,schuckert ---------------------------------------- --------------------- ,hernsand #gj ,thomson ,houston ---------------------------------------- --------------------- ,halle #a1cej #aj ,edison ---------------------------------------- --------------------- #aj1jjj ,hanover to be increased 0 to #bj1jjj ---------------------------------------- --------------------- ---------------------------------------- ---------------------- ,main conductor ,name of overhead ,approximate area ,description ,hours of ,station4 or under-of distribution4 of lighting4 ,supply4 ground4 ---------------------------------------- ---------------------- ,street ,bergen ,overhead lighting and public buildings ---------------------------------------- ---------------------- ,bellegarde ,overhead ---------------------------------------- ---------------------- ,berlin ,under- ,nearly whole ,these instal- ground of business lations part of city supply ,constant 0 0 clubs1 service 0 0 theatres1 0 0 public buildings1 and street lighting ---------------------------------------- ---------------------- ,under- #a1bjj metres ,railway ,breslau ground radius station and mills ---------------------------------------- ---------------------- ,brunswick 0 ---------------------------------------- ---------------------- ,crefeld 0 ,mills and factories ---------------------------------------- ---------------------- ,darmstadt 0 ---------------------------------------- ---------------------- ,dresden 0 ---------------------------------------- ---------------------- ,elberfeld ,under- ,three-wire ground system ---------------------------------------- ---------------------- ,lighting of the ,dusk ,hamburg 0 ,free ,port until dawn ---------------------------------------- ---------------------- ,hernsand ,overhead ---------------------------------------- ---------------------- ,halle ,under- ,stadt ,theatre ground ---------------------------------------- ---------------------- ,hanover 0 #ac1jjj feet ,shops and public,constant radius buildings from station ---------------------------------------- ---------------------- ---------------------------------------- ------------------------ ,charges4 ----------------------------- ,name of ,by ,meter4 ,by yearly ,remarks4 ,station4 fixed amount4 ---------------------------------------- ----------------------- ,bergen ---------------------------------------- ----------------------- ,of fr4 #jd per hour1 or #h francs ,worked by ,bellegarde per month for water power4 #h-;,c4-,p4 ---------------------------------------- ----------------------- ,berlin #fs4 per year fixed charge1 and d4 ,stations at per hour per ,friedrich ,street1 0 #af-;,c4-,p4 lamp2 ,mauer ,street1 0 arc lamps1 #f;d4 and ,schadou ,street4 0 #g;d4 per hour1 and #fjs4 yearly per light ---------------------------------------- ----------------------- ,breslau ---------------------------------------- ----------------------- ,brunswick ---------------------------------------- ----------------------- ,crefeld ---------------------------------------- ----------------------- ,darmstadt ---------------------------------------- ----------------------- ,dresden ---------------------------------------- ----------------------- ,elberfeld ---------------------------------------- ----------------------- ,under construction4 ,hamburg #b block stations1 #a central-station4 ---------------------------------------- ----------------------- ,yearly contract1 ,hernsand which is less than former lighting by oil4 ---------------------------------------- ----------------------- ,halle ---------------------------------------- ----------------------- ,by meter ,hanover to sub- #jdb;d4 per #aj- scribers ,c4-,p4 lamp per for hour2 #je;d4 three per #af-;,c4-,p4 years ---------------------------------------- ----------------------- ---------------------------------------- ------------------- ,approximate ,approximate ,number of ,lights4 length of -------------------- longest ,name of ,incan- ,system main ,station4 descent ,arc4 employed4 supply or ,glow conductor ,lamps4 in miles4 ---------------------------------------- ------------------ ,zippernowsky ,lucerne #hjj high-tension #d current with transformers ---------------------------------------- ------------------ ,lubeck #b1jjj ,edison ---------------------------------------- ------------------ #aa1jjj #baj ,edison ,milan #a1jjj ,zippernowsky 0 ---------------------------------------- ------------------ ,munich #f1ejj #adj ,edison 0 ---------------------------------------- ------------------ ,rome #ad1jjj ,zippernowsky #d ---------------------------------------- ------------------ ,rotterdam #a1jjj ,edison ---------------------------------------- ------------------ ,edison1 ,three- ,st4 ,etienne #c1jjj wire system ---------------------------------------- ------------------ ,edison and ,strassburg #a1hjj #fb ,siemens ---------------------------------------- ------------------ ,stuttgart #a1jfj 0 ---------------------------------------- ------------------ ,schwerin #b1cij 0 ---------------------------------------- ------------------ ,goulard high- ,tivoli #a1jjj #f tension trans- #ah formers ---------------------------------------- ------------------ ,tours #c1ejj ,goulard #c ---------------------------------------- ------------------ ,terni #c1jjj ,zippernowsky ,transformers ---------------------------------------- ------------------ ---------------------------------------- ---------------------- ,main ,description ,hours of conductor ,approximate of lighting4 ,supply4 overhead area of ,name of or under- distribution ,station4 ground4 ---------------------------------------- ---------------------- ,to be extended ,dusk ,lucerne ,overhead throughout ,in hotels until ,lucerne mid- night ---------------------------------------- ---------------------- ,lubeck 0 ---------------------------------------- ---------------------- ,under- #a square mile ,the district is ,milan ground served in a ,constant ,theatre with #dfj similar manner 0 lamps in houses to gas ---------------------------------------- ---------------------- ,munich 0 ,two theatres ---------------------------------------- ---------------------- ,hotels #d ,p4,m4 ,rome 0 and to shops #a ,a4,m4 ---------------------------------------- ---------------------- ,rotterdam 0 ---------------------------------------- ---------------------- ,st4 ,etienne 0 ---------------------------------------- ---------------------- ,under- ,railway station1 ,also a block ,dusk ground and goods station for until ,strassburg and yards1 #hf acres hotel and day- over- area restaurants light head ---------------------------------------- ---------------------- ,stuttgart ,under- ,theatre ground ---------------------------------------- ---------------------- ,schwerin 0 0 ---------------------------------------- ---------------------- ,principally ,tivoli ,overhead street lighting ---------------------------------------- ---------------------- ,tours 0 ---------------------------------------- ---------------------- ,terni ,town lighting ---------------------------------------- ---------------------- ---------------------------------------- ------------------------- ,charges4 ,name of ------------------------------ ,station4 ,by ,meter4 ,by yearly ,remarks4 fixed amount4 ---------------------------------------- ------------------------ ,lucerne ,motive power1 water4 ---------------------------------------- ------------------------ ,lubeck ---------------------------------------- ------------------------ ,arc and ,installation charge incan- per lamp ,milan descent per #aj candles1 #hs4 d4 per 0 #af 0 #bhs4 ampre- 0 #cb 0 #efs4 hour ,arc lamp #b per annum rent ---------------------------------------- ------------------------ ,munich ---------------------------------------- ------------------------ ,of #bjh;d4 ,the installation is ,rome per #af ,c4-,p4 owned by the gas lamp per hour company4 ---------------------------------------- ------------------------ ,rotterdam ---------------------------------------- ------------------------ #cs4 #e;d4 per #af ,st4 ,etienne ,meter ,c4-,p4 lamp per month1 also fixed sum of #bs4 #aa;d4 per lamp ---------------------------------------- ------------------------ ,net cost of lighting station1 including #ab per cent4 for ,carried out by the interest and renewal4railway company4 ,the ,strassburg --,arc lamps1 cost is estimated at #c;d4 per hour2 one-third less than #af ,c4-,p4 glow lamps1 gas4 #jdb;d4 per hour2 #aj ,c4-,p4 glow lamps1 #j4cb;d4 per hour2 #h ,c4-,p4 glow lamps1 #jbi;d4 per hour ---------------------------------------- ------------------------ ,stuttgart ,one central-station4 ,one block station4 ---------------------------------------- ------------------------ ,schwerin ---------------------------------------- ------------------------ ,motive power1 water2 ,tivoli yearly contract for street lighting4 ---------------------------------------- ------------------------ ,subscribers at #bs4 ,three distributing ,tours #i;d4 per #af ,c4-,p4 stations at work1 lamp per month to be increased to ten4 ---------------------------------------- ------------------------ ,terni ,charge #jd;d4 to #ac;d4 per hour according to ,c4-,p4 ---------------------------------------- ------------------------ ---------------------------------------- -------------------- ,approximate ,approximate ,number of ,lights4 length of --------------------- longest ,name of ,incan- ,system main ,station4 descent ,arc4 employed4 supply or ,glow conductor ,lamps4 in miles4 ---------------------------------------- ------------------- ,treviso #hjj ,zippernowsky transformers ---------------------------------------- ------------------- ,turin #a1jjj #ajj ,edison ---------------------------------------- ------------------- ,brush ,temesvar #gfj machines2 #b ,lane ,fox lamps ---------------------------------------- ------------------- ,crompton ,low- tension ,vienna #h1jjj dynamos with battery transformers ---------------------------------------- ------------------- ---------------------------------------- ---------------------- ,main conductor ,approximate ,hours ,name of overhead area of ,description of ,station4 or under- distribution of lighting4 ,supply4 ground4 ---------------------------------------- ---------------------- ,treviso ,overhead ,town lighting4 ---------------------------------------- ---------------------- ,turin ,under- ,street lighting ground by arc lamps ---------------------------------------- ---------------------- ,about #cg miles ,street ,dusk ,temesvar ,overhead of streets lighting until chiefly dawn ---------------------------------------- ---------------------- ,opera house1 ,vienna ,under- ,court theatre1 ground and municipal buildings ---------------------------------------- ---------------------- ---------------------------------------- ----------------------- ,charges4 --------------------------- ,name of ,by ,by yearly ,remarks4 ,station4 ,meter4 fixed amount4 ---------------------------------------- ---------------------- ,treviso ---------------------------------------- ---------------------- ,turin ,thomson-,houston arc lamps ---------------------------------------- ---------------------- ,street lighting1 #ae kreutzer per #af-;,c4-,p4 ,temesvar lamp per hour ,private consumers1 #aha kreutzer ---------------------------------------- ---------------------- ,this installation is ,by contract at a being put down by ,vienna price about double the gas company gas which lights the city4 ---------------------------------------- ---------------------- ,,index4 ,arc ,lamps1 ---- places where suitable1 #aj4 ---- charges for1 #aj4 ---- at ,milan1 #dg4 ,accumulators1 ---- at ,kensington ,court1 #fi4 ---- at ,vienna1 #gf4 ,birmingham wire gauge resistance table1 #aje4 ---- in ,french measurements1 #ajf4 ,central-stations1 ---- ,siemens' suggestion for1 #a4 ---- at ,philadelphia1 #b4 ---- block1 #c4 ---- construction1 #c4 ---- selection of district for1 #d4 ---- relation between daily output and capacity1 #g4 ---- loss in1 #ae4 ---- at ,deptford1 #ca4 ---- at ,eastbourne1 #ca4 ---- at ,brighton1 #cb4 ---- at ,tours1 #cb4 ---- at ,vienna1 #gf4 ---- position of1 #af4 ---- in ,united ,states1 #ag4 ---- at ,grosvenor ,gallery1 #bg4 ---- ,kensington ,court1 #bj1 #fh4 ---- methods of lighting from1 #bj4 ---- tables showing cost of1 #hf1 #hg4 ,cost of gas compared with electricity1 #h4 ,cost of kerosene1 #i4 ,cost of arc lighting1 #aj4 ,conductors1 ---- relative size of1 for different systems1 #bb4 ---- arrangement of1 at ,grosvenor ,gallery1 #bh4 ---- primary conductors at ,grosvenor ,gallery1 #cj4 ---- diagram of network system of1 at ,milan1 #df4 ---- diagram of multiple series system at ,temesvar1 #fj4 ---- conduits for1 in ,new ,york1 #ib1 #ic1 #id4 ,distribution of ,electricity1 ---- ,edison parallel system1 #da4 ---- ,edison feeders1 #db4 ---- three-wire system1 #dc4 ---- series system1 #eb4 ---- ,bernstein system1 #eg4 ---- multiple series system1 #eh4 ---- by means of secondary batteries1 #fe4 ---- system of1 at ,kensington ,court1 #fi4 ,dynamotors1 #gi4 ---- ,swinburne's ,compound1 #hc4 ,electric ,lighting1 ---- as an investment1 #c1 #i1 #ig4 ---- people who most readily take it up1 #d4 ---- relation between number of lights used and number fixed1 #d1 #e4 ---- cost of1 to householder1 #e4 ---- diagram of1 in ,london district1 #f4 ---- diagram of1 at ,cincinnati1 #g4 ---- charges for1 #h4 ---- description of arc and glow1 #i4 ---- at ,tilbury ,docks1 #ah4 ---- at ,victoria ,station1 #ah4 ---- at ,paddington ,station1 #ai4 ---- relative cost of1 for direct and transformer systems1 #ba1 #bg4 ---- at ,lucerne1 #cd4 ---- at ,milan1 #cd1 #dd4 ---- cost of1 at ,milan1 #dh4 ---- at ,berlin1 #eb4 ---- cost of1 at ,berlin1 #ec4 ---- ,bernstein system of1 #ee4 ---- diagram of1 system at ,colchester1 #fg4 ---- working cost of1 at ,athenum ,club1 #hh4 ---- working cost of1 at ,naval and ,military ,club1 #hi4 ---- working cost of1 at ,south ,kensington ,museum1 #hi4 ---- working cost of ,thomson-,houston system of1 in an ,american city1 #ij4 ,experiment at the ,teatro dal ,verone1 #cd4 ,faults1 discovery of1 #ea4 ,gas ,lights1 ---- heat from1 advantages and objections1 #c4 ---- number used and fixed1 #d4 ---- cost of1 at ,berlin1 #ec4 ---- cost of1 to householder1 #e4 ,glossary1 #ajg4 ,incandescent ,lamps1 ---- number obtained per electrical ,,hp41 #h4 ---- illustration of1 #aa4 ---- candle-power of1 #aa4 ---- consumption of energy in1 #aj1 #fc4 ---- life of1 #aa4 ---- blackening of1 #ab4 ---- at ,temesvar1 #fc4 ,lighting1 ---- number of hours of1 per annum1 #d4 ---- cost of1 to ,london householder1 #e4 ---- diagram of1 in ,london district1 #f4 ---- diagram of1 at ,cincinnati1 #g4 ---- diagram of1 #ac4 ---- relative cost of1 with direct and transformer system1 #bb4 ---- relative cost of1 by electricity and gas1 #ia4 ,lucigen light1 the1 #ii4 ---- cost of working1 #ajj4 ,machinery at ,grosvenor ,gallery1 #bi4 ,motors1 ,electric1 #ci4 ---- diagram showing power supplied to1 in ,boston1 #dj4 ---- purposes used for1 in ,america1 #ci4 ,meters1 ,electric1 ---- the ,edison1 #di4 ---- the ,aron1 #ed4 ,mackenzie's conduits for electric light cables1 #ie4 ,priestman's petroleum engine1 #ih4 ,regulation of ,e4 ,m4 ,f4 at ,grosvenor ,gallery1 #bi4 ,regulation of ,e4 ,m4 ,f4 at ,milan1 #dd4 ,rent of meters at ,milan1 #di4 ,rent of meters at ,berlin1 #ec4 ,regulators for secondary batteries1 #gf4 ,resistance of ,copper ,wire1 #aje1 #ajf4 ,speed indicators at ,grosvenor ,gallery1 #bi4 ,safety fuses at ,grosvenor ,gallery1 #ca4 ,safety fuses at ,milan1 #dg4 ,switch1 double pole1 #gb4 ,table ,i4 showing cost of laying conductors1 #gd1 #ge4 ,table ,,ii4 showing cost and maintenance of plant1 #hf1 #hg4 ,table showing resistance1 c41 of copper wire1 #aje1 #ajf4 ,table showing principal electric lighting stations in ,great ,britain1 #aaf-aai4 ,table showing principal electric lighting stations on the ,continent1 #abj-abe4 ,terms1 explanation of1 #ajg-aae4 ,transformers1 ---- application of1 #bg4 ---- diagram of ,ruhmkorff type of1 #bc4 ---- description of ,ruhmkorff type of1 #bc4 ---- arrangements of circuits of1 #bd4 ---- two classes of1 #bd4 ---- ,kapp ,snell1 #bg4 ---- distribution of electricity by means of1 #ba4 ---- prevention of shocks from1 #cj4 ---- ,westinghouse converters1 #ce4 ---- potential used in1 #ch4 ---- direct current1 #gi4 ---- comparison between alternate and direct current1 #hj4 ---- ,swinburne's dynamotor1 #hc4 ---- advantages of ,zippernowsky-,deri system of1 #cd4 ,turbines working the dynamos at ,tivoli1 #cb4 ,turbines working the dynamos at ,lucerne1 #cc4 ,useful ,notes1 #aja-ajc4 ---- incandescent lights1 #ajb4 ---- arc lighting of works1 #ajb4 ---- approximate cost1 #ajb4 ---- wire running1 #ajc4 ---- ,electrical ,measurements1 #ajd4 ,westinghouse system1 #ce4 ---- at ,pittsfield1 #cg4 ,wires overhead or underground1 #ia4 ,illustration ,,london3 ,,printed ,,by ,,william ,,clowes ,,and ,,sons1 ,,limited1 ,,stamford ,,street ,,and ,,charing ,,cross4 ,,the ,,house-,,to-,,house ,electric ,light ,supply ,co41 ,ld4 7,,model ,,central ,,electric ,,lighting ,,station1 ,,kensington1 ,,adjoining ,,the ,,west ,,brompton ,,station ,,on ,,the ,,metropolitan ,,district ,,railway7 ,are prepared to assist the formation of ,,local ,,electric ,,light ,,companies1 and to erect ,,central-,,stations for the distribution of ,electricity in any part of the ,kingdom4 ,estimates for ,complete ,sets of ,plant furnished free of charge4 ,,william ,,lowrie1 ,engineer4 ,h4 ,st4 ,,john ,,winkworth1 ,secretary1 #aag1 ,bishopsgate ,street1 ,london1 ,e4,c4 ,,by ,,the ,,same ,,author4 ,,precautions ,,to ,,be ,,adopted ,,on ,,introducing ,,the ,,electric ,,light4 ,,insurance ,,rules1 c41 ,,with ,,notes ,,on ,,the ,,prevention ,,of ,,fire ,,risks4 ,illustrated4 ,price #bs4 #j;d4 ,,the ,,supply ,,of ,,electricity ,,by ,,local ,,authorities4 ,demy #hvo4 ,illustrated4 ,price #as4 ,,district ,,electricity ,,supply4 ,,central ,,supply ,,stations ,,worked ,,on ,,the ,e4,p4,s4 ,,automatic ,,system ,,for ,,the ,,public ,,supply ,,of ,,electricity ,,from ,,storage ,,batteries4 ,descriptive ,pamphlet ,free4 ,,epitome ,,of ,,the ,,system4 ,the generating plant is all placed in a conveniently situated building within or without the ,district to be ,lighted4 ,convenient ,sub- or ,storage-,stations are selected throughout this ,district1 and contain sufficient ,accumulators to supply the maximum demand4 ,the ,batteries in each of these ,storage-,stations are recharged in series1 one-half at a time1 throughout the ,system during the period of minimum demand1 and by the evening are all full and ready to cope with the heavy night work4 ,the whole of the charging1 discharging1 and regulating apparatus is worked automatically4 ,,advantages ,,of ,,the ,,system4 ,reliability4--,the ,light is solely derived from ,storage1 and is absolutely steady4 ,there is no connection whatever between the ,lamp and ,moving ,machinery4 ,the ,supply is continuous day and night4 ,economy in ,prime ,outlay4--,the proportion of ,engine ,power in use to the power required for maximum supply is only about one- third1 while any system1 if running direct1 requires a large portion of the plant to be duplicated4 ,economy in ,working4--,the generating station is only at work a definite number of hours during the daytime1 after which period the plant may be let out or utilized for other purposes1 such as motive power1 c4 ,electro ,motors for all purposes can be driven from the ordinary discharge mains4 ,this is impossible where alternating currents are employed4 ,,guarantee4--,the ,e4,p4,s4 ,co4 undertake to supply all the necessary renewals for the ,storage ,batteries in use in the above system at the rate of #ab per annum on the actual first cost of the ,batteries4 ,e4,p4,s4 ,accumulators are already in use at the following ,central-,stations3--,vienna2 ,berlin2 ,cadogan 7,london72 ,norwich2 ,taunton2 ,leamington2 ,st4 ,austell2 ,detroit1 ,u4,s4,a42 ,allentown1 ,u4,s4,a42 ,blenheim1 ,u4,s4,a42 ,haverford1 ,u4,s4,a42 ,delaud1 ,u4,s4,a4 ,districts ,surveyed1 ,plans1 ,specifications and ,tenders submitted by the ,,electrical ,,power ,,storage ,,company1 ,,ltd41 #d ,,great ,,winchester ,,street1 ,,london1 ,e4,c4 ,,telegrams1 8,,storage1 ,,london40 ,,telephone ,,no4 #cch4 ,,anglo-,,american ,brush ,electric ,light ,corporation1 ,ltd4 ,,manufacturers ,,of ,,brush ,,arc ,,dynamos ,,and ,,lamps4 ,victoria ,incandescence ,dynamos and ,lamps4 ,,alternate ,,current ,,dynamo ,,machines4 ,transformers4 ,motors4 ,,all ,,fittings ,,for ,,arc ,,and ,,incandescence ,,lighting1 ,etc4 ,,contractors ,,for ,,private ,,installations ,,of ,,electric ,,light4 ,,central ,,electric ,,light ,,stations4 ,,installations ,,on ,,shipboard4 ,,electrical ,,railways ,,and ,,tramways4 ,railway ,train ,lighting by ,electricity4 ,,installations ,,for ,,transmission ,,of ,,power1 ,etc4 ,etc4 ,the ,corporation are prepared to undertake the establishment of ,central ,electric ,lighting ,stations on the high or low-tension continuous current systems1 with or without accumulators1 or on the alternating current system with transformers1 as may be best suited to the requirements of each particular case4 ,the ,corporation invite enquiries from ,municipalities1 ,local ,gas or ,electrical ,companies1 or owners of ,blocks of ,houses or ,shops1 for the erection of ,central ,generating ,stations1 and the supply of ,electricity1 either on their own account1 or upon such terms and conditions as may be agreed upon4 ,full particulars on application to-- ,,the ,,secretary1 #aab1 ,,belvedere ,,road1 ,,london1 ,s4,e4 ,,united ,,electrical ,,engineering ,,company1 ,,limited4 ,the company have exceptional facilities for carrying out contracts at home or abroad in the various branches of ,electrical ,engineering4 ,they own several valuable patents in connection with the distribution of ,electricity and its application to industrial and domestic purposes2 they are not1 however1 restricted to any special system1 and give particular attention to providing those appliances which are best adapted to the purposes in view4 ,the ,works are equipped for manufacturing1 testing1 and repairing1 and form a valuable auxiliary to extensive contract work1 enabling the ,company to give prompt attention to the demands of their clients4 ,contractors for ,,central ,,electric ,,supply ,,stations4 ,,electric ,,light ,,installations4 ,,transmission ,,of ,,power4 ,,the 8,,telpher0 ,,system ,,of ,,cheap ,,transport4 ,,electric ,,trams ,,railways1 c4 ,please apply for complete list of ,electric ,light and ,power ,supplies to-- #cf1 ,,albert ,,embankment1 ,,london1 ,s4,e4 ,,carbon ,,works1 ,,barnsley4 ,,the ,,globe ,,electrical ,,and ,,engineering ,,company4 ,,electrical ,,and ,,general ,,engineers4 ,illustration ,contractors for ,electric ,lighting4 ,and ,manufacturers of ,dynamos1 ,lamps1 ,switches1 ,cut-outs1 and every ,appliance used in the ,installation of ,electric ,light4 ,,no4 #a ,,department comprises all ,electric ,light ,fittings1 also ,ornamental ,electroliers1 ,pendants1 ,brackets1 ,ceiling ,plates1 or ,rosettes1 ,globe ,lamps and ,globe ,lamp ,holders1 also ,glass ,shades and ,fringes in coloured glass of many varieties4 ,,no4 #b ,,department4 ,this includes the well known brand of ,globe ,carbon ,rods and ,battery ,plates1 ,galvanic ,batteries of all descriptions1 ,battery supplies or materials such as terminals1 zinc1 crushed carbon1 chemicals1 jars1 and porous pots4 ,measuring ,instruments1 ,galvanometers1 patent ,speed ,gauges1 ,ammeters and ,voltmeters--the accuracy of same certified and laboratory test supplied4 ,,no4 #c ,,electrical ,,engineering4 ,dynamos1 ,alternating and ,continuous ,current4 ,transformers1 ,cable--plain1 copper1 lead coated2 also of the special high insulation required by ,london ,electrical ,supply ,co4's rules4 ,sundries for ,central-,station ,installation4 ,special ,list will be sent on application4 ,telephones and ,transmitters4 ,sundries for ,telephone ,installations4 ,belting1 ,oils1 ,waste1 ,paint1 ,patent ,jointing ,mastic1 c41 are kept in ,stock1 also ,cable1 ,silk and ,cotton ,covered ,wire4 ,address3--,the ,,manager1 ,offices--#g1 ,,carteret ,,street4 ,supply ,stores3 #bj1 ,dartmouth ,street1 ,westminster1 ,s4,w4 ,telegraphic ,address1 8,globulous1 ,london40 ,,carbon ,,works1 ,,barnsley4 ,,the ,globe ,electrical ,engineering ,company4 ,,carbon ,,cutters ,,and ,,grinders4 ,,carbon ,,rods4 ,illustration ,,carbon ,,plates4 ,,electric ,,light ,,carbon ,,rods 7,fig4 #f71 cored and solid1 coppered and plain4 ,all sizes in stock from #d to #dj4 ,makers of ,sir ,james ,douglas's ,rods 7,fig4 #d71 as used by the ,trinity ,house4 ,,carbon ,,plates for ,leclanch ,batteries1 etc4 7,fig4 #c71 ,consolidated ,battery ,plates1 made to withstand nitric acid or bichromate1 can be supplied up to #ac;ins4 #aj;ins4 out of stock1 and larger sizes to order4 ,,carbon ,,cells ,,and ,,cylinders 7,figs4 #a1 #b1 and #e71 of all descriptions4 ,experimental ,carbon ,goods of every description made to ,order4 ,,prices ,,on ,,application4 ,offices3--#g1 ,,carteret ,,st41 ,,westminster1 ,s4,w4 ,,the ,,gulcher ,,electric ,,light ,,power ,,co41 ,,ltd41 ,,battersea ,,foundry1 ,,battersea1 ,,london1 ,s4,w4 ,manufacturers of ,electrical ,machinery ,,of ,,every ,,description4 ,contractors to ,h4,m4 ,,navy1 ,h4,m4 ,,war ,,department1 ,sir ,w4 ,g4 ,,armstrong ,,co41 ,,oudh ,,and ,,rohilkund ,,railway ,,co41 etc41 etc4 ,illustration ,,the ,,company ,,supply-- ,,dynamos4 ,series1 ,shunt1 and ,compound ,wound4 ,,arc ,,lamps4 ,projectors1 ,search ,lights1 etc4 ,,switch ,,boards and ,fittings4 ,,alternating ,,current ,,dynamos4 ,,transformers4 ,,secondary ,,batteries4 ,,complete ,,installations for lighting ,,towns1 ,,public ,,buildings1 ,,mills1 ,,factories1 ,,ironworks1 and ,,collieries1 also ,,private ,,houses and ,,mansions4 ,,sole ,,contractors for the ,,permanent ,,lighting of the ,,crystal ,,palace1 ,sydenham1 and the ,,royal ,,aquarium1 ,,westminster1 also the ,,city of ,,wellington1 ,new ,zealand4 ,,woodhouse ,,rawson1 ,,limited4 ,electrical ,engineers and ,contractors1 ,,for ,,the ,,lighting ,,of ,,cities1 ,,towns1 ,,factories1 ,,mills1 ,,and ,,private ,,residences4 ,,complete ,,central-,,station ,,plant4 ,houses ,wired and ,fitted throughout for connection to ,central-,station ,circuits4 ,,estimates ,,on ,,application4 ,,good ,,work ,,at ,,moderate ,,prices4 #aa1 ,,queen ,,victoria ,,street1 ,,london1 ,e4,c4 ,contractors to the ,chief ,exhibitions1 ,stock ,exchange1 ,messrs4 ,w4 ,h4 ,smith ,sons1 ,peak1 ,frean ,co41 ,crosse ,blackwell1 ,grosvenor ,gallery1 c41 c4 ,,the ,orient ,electric ,light ,company ,,limited4 ,illustration ,contractors for the supply of ,electric ,lighting ,plant for ,private ,houses1 ,public ,buildings1 ,factories1 ,towns1 c41 on the most approved system and at moderate cost4 ,,quotations ,,given ,,for ,,temporary ,,installations4 ,central-,stations ,fitted ,out1 and ,negotiations carried on for same4 ,,estimates ,,and ,,quotations ,,free4 ,london ,offices3 #b1 ,east ,india ,avenue1 ,e4,c4 ,,agents ,,abroad3 ,messrs4 ,,gillanders1 ,,arbuthnot ,,co4 ,calcutta and ,rangoon ,messrs4 ,,gordon1 ,,woodroffe ,,co4 ,madras4 ,messrs4 ,,ewart1 ,,latham ,,co4 ,bombay4 ,crown #hvo41 #abh pp41 ,limp cloth1 #dj ,illustrations4 ,price #bs4 #f;d4 ,,precautions ,,to ,,be ,,adopted ,,on ,,introducing ,,the ,,electric ,,light4 ,,with ,,notes ,,on ,,the ,,prevention ,,of ,,fire ,,risks4 ,,contents4--,fire ,risk ,committee--,resistance of ,conductors--,glow ,lamps--,sizes of ,main and ,branch ,conductors--,standard and ,birmingham ,wire ,gauge--,factors for ,calculation--,running of ,wires--,switches--,connectors and ,joints--,insulators--,short ,circuit--,cut-out1 ,fusible1 and ,automatic--,lamp ,holders--,life of ,lamps1 ,electrical ,governor1 ,speed ,gauge--,testing ,insulation--,fires and ,accidents from ,electric ,current--,specification for ,electric ,lighting--,instructions for ,working--,phnix ,fire ,office ,rules--,american ,fire ,office ,rules--,electrical ,measurements--,resistance of ,copper and ,german ,silver--,english and ,french ,measure--,rules for ,fusible ,mica-,foils--,rules for ,direction of ,current--,number of ,electric ,lights to compare with ,gas--,motive ,power1 ,steam1 ,gas--,motive ,power1 ,water--,explanation of ,terms--,price ,list4 ,,opinions ,,of ,,the ,,press4 ,the ,builder4 8,mr4 ,hedges points out clearly the risks that are inseparable from slovenly work and incompetent handling1 and gives clear directions for carrying the main and branch conductors and the lamp wires1 and for calculating the sizes of the various leads according to the number of lights to be worked4 ,he insists very properly that some regular system should be followed1 so that it should always be known which is the positive and which the negative wire1--in other words1 which wire leads from the machine to the lamps1 and which is the return4 ,in addition1 however1 to showing this by mere position1 i4e41 by placing the positive wire on the left side of the negative if vertical1 and under it if horizontal1 we should strongly recommend that the insulating covering should be of different colours on the two wires1 and thus any accidental displacement would not be of consequence40 ,revue ,internationale de l',electricit4 8,ce petit livre sans prtention contient une grande quantit de renseignements pratiques4 ,tous ceux qui s'occupent d'clairage lectrique trouveront grand profit le consulter4 8,dans les quatre-vingts pages que contient ce travail1 l'auteur a su rassembler toutes les indications ncessaires et utiles pour effectuer les installations4 ,il n'tait pas possible de grouper d'une manire plus logique1 plus claire et plus concise les rgles suivre pour assurer le bon fonctionnement d'une installation d'clairage4 8,l'auteur s'est tendu surtout sur la description et l'installation des appareils de sret1 sur la pose des conducteurs et sur les diamtres leur donner1 sur l'essai des circuits1 etc4444 8,un petit dictionnaire1 donnent l'explication des terms techniques1 complte d'une manire heureuse ce petit guide qui sera consult avec autant de profit que bien d'autres ouvrages plus tendus et conus dans un esprit moins pratique4 8,,aug4 ,m40 ,copies of the above can be obtained from ,the ,globe ,electrical and ,engineering ,company1 #g1 ,,carteret ,,street1 ,,westminster1 ,s4,w4 ,manufacturers of ,electrical ,supplies4 ,e4 ,,and ,f4 ,n4 ,,spon1 ,,london4 ,crown #hvo4 #aef pp4 ,cloth gilt4 ,price #cs4 ,useful ,information on ,electric ,lighting4 ,,embodying ,,the ,,rules ,,of ,,the ,,fire ,,risk ,,committee ,,and ,,the ,,electric ,,lighting ,,bill2 ,,also ,,plain ,,directions ,,for ,,the ,,working ,,of ,,electric ,,lamps ,,and ,,dynamo ,,machines4 ,,by ,,killingworth ,,hedges1 ,m4,i4,c4,e41 ,m4 ,soc4 ,telegraph ,engineers1 ,f4,c4,s4 ,,contents4--,introductory ,remarks--,the ,production of ,electricity--,the ,voltaic ,arc--,division of the ,electric ,light--,machines or ,generators--,power required1 and ,motors--,application of the ,electric ,light--,choice of a ,system--,electrical ,measurement--,cost of ,working--,result of ,various ,installations--,measurement of ,light and ,current--,storage of ,electricity and ,transmission of ,power--,conclusion--,useful ,tables and ,memoranda4 ,the ,graphic1 8,at the present time1 when the question of illumination by electricity is fully under discussion1 a third edition of ,mr4 ,killingworth ,hedges' ,useful ,information on ,electric ,lighting is doubly welcome4 ,the little work is now fully brought up to date1 and gives a plain1 straightforwardly written account of the various forms of the arc and incandescent lamps1 and1 indeed1 of the general system of electric lighting4 ,thus a very fair idea of the principle may be gathered by the general reader1 who will find it a welcome companion when visiting the ,electrical ,exhibition1 while the manufacturer in search of a practicable light for his workshop will gain valuable information from the various hints conveyed in its pages4 ,to the scientific student also the work will be exceedingly useful1 if only from the handy memoranda and tables in the appendix4 ,altogether the book is the best of the kind that we have yet seen1 and we cannot refrain from hoping that ,mr4 ,killingworth ,hedges may see fit to bring out a more compendious and detailed work on the subject1 with which he is so eminently competent to deal40 ,also1 by the same ,author1 demy #hvo4 ,illustrated1 #cb pp4 ,paper4 ,price #as4 ,the ,supply of ,electricity by ,local ,authorities4 ,,read ,,at ,,the ,,annual ,,meeting ,,of ,,the ,,association ,,of ,,municipal ,,engineers ,,and ,,surveyors1 ,,oxford1 #ahhc4 ,all ,mr4 ,hedges' books are sent post free on receipt of postal order1 by the ,,globe ,,electrical ,,and ,,engineering ,,company1 ,supply ,stores1 #g1 ,carteret ,street1 ,westminster1 ,s4,w4 ,,the ,,barnsley ,,carbon ,,company4 ,wholesale ,manufacturers of ,,pure ,,carbon ,,points1 ,,candles1 ,,and ,,battery ,,plates ,,of ,,every ,,description4 ,,carbon ,,cutters ,,and ,,grinders4 ,,carbon ,,works3 ,,barnsley1 ,,yorkshire4 ,,london ,,office3 #g1 ,carteret ,street1 ,westminster1 ,s4,w4 ,j4 ,,edmundson ,,co41 ,,limited1 ,engineers ,electricians1 #ai1 ,,great ,,george ,,st41 ,,westminster1 ,s4,w4 ,electric ,lighting for ,country and ,town ,mansions1 c4 ,j4 ,,edmundson ,,co41 invite an inspection of their ,complete ,system of ,lighting ,,country and ,,town ,,mansions1 by means of ,incandescent ,electric ,lights4 ,a ,,complete ,,installation consisting of ,,dynamo ,,machine1 ,,engine1 ,,storage ,,battery and ,,lamps1 may be seen working at ,j4 ,e4 ,co4's ,,show ,,rooms1 #ai1 ,,great ,,george ,,street1 ,,westminster1 where all information1 including ,estimates of ,cost1 c41 may be obtained4 ,,estimates ,,also ,,given ,,for ,,temporary ,,lighting ,,by ,,means ,,of ,,storage ,,batteries1 ,,for ,,balls1 ,,receptions1 c4 ,,special ,,agents ,,for ,,edison ,,swan ,,lamps4 ,special ,terms to the ,trade4 ,,manufacturers ,,of ,,electroliers1 ,,brackets1 ,,and ,all ,descriptions of ,electric ,light ,fittings4 ,central-,station ,lighting4 ,illustration ,,the ,,kapp ,,transformer4 ,,the ,,connaught alternating current ,dynamo4 7,,kapp',s ,,patent47 ,,sharp ,,and ,,kent1 ,,engineers ,,and ,,electricians1 ,connaught ,mansions1 ,victoria ,st41 ,westminster1 ,s4,w4 ,,telegraphic ,,address-- 8,,megavolt1 ,,london40 ,,telephone1 #c1abe ,,dr4 ,,arons ,,electricity ,,meters ,for ,alternate and ,continuous ,current4 ,used in all the most ,important ,central-,stations in the ,world4 ,illustration ,,the ,,general ,,electric ,,co41 7,g4 ,,binswanger ,,co47 ,manufacturers and ,suppliers of ,the ,,apostle ,carbons4 ,china and ,glass ,ware1 ,switches1 ,lamps1 ,cables1 ,casings1 c4 ,the best without exception4 ,in great variety4 ,electrical ,fittings of every description4 ,,london3 ,,the ,,general ,,electric ,,co41 #e1 ,,great ,,st4 ,,thomas ,,apostle1 ,,london1 ,e4,c4 ,telegrams3 8,electricity40 ,telephone3 8#ahhg40 ,,manchester3 ,,manchester ,,electric ,,works ,,co41 7,g4 ,,binswanger1 ,managing ,director71 #de1 ,,chapel ,,street1 ,,salford1 ,,manchester4 ,telegrams3 8,induction40 ,,the ,,globe ,,electrical ,,and ,,engineering ,,company4 ,offices3--#g1 ,,carteret ,,st41 ,,westminster1 ,s4,w4 ,,manufacturers ,,of ,,hedges' ,,patent ,,safety ,,catches1 ,,or ,,cut-,,outs1 ,,with ,,fusible ,,safety ,,plugs ,,and ,,of ,,albo ,,metal ,,mica-,,foils4 ,illustration ,,directions ,,for ,,inserting ,a ,,spare ,,mica-,,foil4--,undo the ,contact ,screws1 lift the ,contact ,pieces and place ,foil fairly under1 and screw down1 taking care not to jam the ,mica on to the ,foil1 which should be loose1 so as to allow for expansion4 ,certificate from the ,vienna ,exhibition1 which was protected throughout by 8,hedges' ,patent ,fuses40 ,,translation4 ,,the ,,patent ,,hedges' ,,cut-,,outs have found a useful sphere of employment in the labours of the ,technical ,scientific ,commission1 and their construction has proved itself most admirably adapted to the ends in view4 ,the ,president of the ,technical ,scientific ,commission1 ,,vienna1 #acth ,may1 #ahhd4 7,signed7 ,f4 ,,stefan4 ,w4 ,t4 ,,goolden ,,co41 ,electrical ,engineers1 ,contractors to ,her ,majesty's ,government and the ,principal ,railway ,companies4 ,sole ,manufacturers of the ,connaught 7,kapp's ,patent7 ,alternating ,current ,dynamo and ,transformers2 ,,goolden-,,ravenshaw ,,continuous ,,current ,,dynamo2 ,electric ,motors for all purposes2 ,,measuring ,,instruments2 ,,cardew ,,voltmeters 7,the only ,reliable ,instruments for ,alternating ,currents72 ,evershed ,patent ,gravity ,voltmeters and ,ammeters 7,not affected by the proximity of dynamos74 ,complete ,estimates furnished for ,central-,stations1 ,plant for ,alternating and ,direct ,currents1 or for ,batteries1 ,engines1 ,boilers1 etc41 by the ,best ,makers only1 and of the most economical types4 ,,all ,,plants ,,supplied ,,can ,,be ,,tested ,,at ,,our ,,own ,,works4 ,offices and ,works3 ,,woodfield ,,road1 ,,westbourne ,,park1 ,,london1 ,w4