786 eepout — 1888. 



financial bubbles transferred much gold from the pockets of the weak to the coffers 

 of the unscrupuloas ; hasty legislation in 1882 restricted the operations of the 

 cautious and the wise; and the prejudice arising- from all these causes has, perhaps 

 fortunately, delayed the general introduction of electricity ; but now legislation has 

 been improved, experience has been gained, confidence is being restored, and in this 

 beautiful town of Bath fifty streets are about to be lighted, and we see everywhere 

 around and about us in our English homes the pure glow lamp replacing filthy gas 

 and stinking oil. The economical distribution of the electric current over large 

 areas is annually receiving a fresh impetus. The expensive systems defined in the 

 Act of Parliament of 1882 have entirely disappeared. Hopkinson in England and 

 Edison in America showed how a third wire reduced the weight of copper needed 

 by 66 per cent. Gaulard and Gibbs in 1882 showed how tlie conversion of alternate 

 currents of high electromotive force to currents of low electromotive force by 

 simple induction coils would enable a mere telegraph wire to convey sufficient 

 electricity to light a distant neighbourhood economically and efficiently. Lane Fox 

 in 1879 showed how the same thing could be done by secondary batteries ; and 

 Plante, Faure, Sellon, and Parker have done much to prove how batteries can be 

 made to solve the problem of storage ; while King and Edmunds have shown how 

 the distribution by secondary batteries can be done as economically as by secondary 

 generators. The Grosvenor Gallery Co. in London have proved the practicability 

 of the secondary generator principle by nightly supplying 24,000 glow lamps 

 scattered over a very wide area of London. The glow lamp of Edison, which in 

 1881 required .5 watts per candle, has been so far improved that it now consumes 

 but 2^ watts per candle. The dynamo, which in the same year weighed .50,000 lbs., 

 absorbed 150 horse-power, and cost 4,000^. for 1 ,000 lamps, now weighs 14,000 lbs., 

 absorbs 110 horse-power, and costs 500/. for the same production of external 

 energy ; in other words, its commercial output has been increased nearly six times, 

 while its prime cost has been diminished eight times. 



The steam-engine has received equal attention. The economy of the electric 

 light when steam is used depends almost entirely on the consumption of coal. 

 With slow-speed low-pressure engines one kilowatt (1,000 watts, 1^ horse-power) 

 may consume 12 lbs. of coal per hour : in high-speed high-pressure triple-expansion 

 condensing engines it need not consume more than 1 lb. of coal per hour. VVillans 

 and Robinson have actually delivered from a dynamo one kilowatt by the con- 

 sumption of 2 lbs. of coal per hour, or by the condensation of 20 lbs. of steam. 



There is a great tendency to use small economical direct-acting engines in place 

 of large expensive engines, which waste power in couutershafting and belts. 

 Between the energy developed in the furnace in the form of heat and that dis- 

 tributed in our rooms in the form of light there have been too many points of 

 waste in the intermediate operations. These have now been eliminated or reduced. 

 Electricity can now be produced by steam at '3d. per kilowatt per hour. The kilo- 

 watt-hour is the Board of Trade unit as defined by the Act of 1882, for which the 

 consumer of electric energy has to pay. Its production by gas engines costs 6d. per 

 kilowatt-hour, while by primary batteries it costs 3s. per kilowatt-hour. The 

 Grosvenor Gallery Company supply currents at 7{f/. per kilowatt-hour ; a 20 candle- 

 power lamp consuming .3 watts per candle, and burning 1,200 hours per annum, 

 expends 82,000 watt-hours or 82 kilowatt- hours, and it costs, at 7^d. per unit, 50s. 



?er annum. If the electricity be produced on the premises, as is the case in the 

 'ost Office, in the House of Commons, and in many large places, it would cost 

 20s. 6d. per annum. I have found from a general average under the same circum- 

 stances and for the same light in the General Post Office in London that an electric 

 glow lamp costs 22s. and a gas lamp 18s. per annum. The actual cost of the pro- 

 duction of one candle light per annum of 1,000 hours is as follows : — 



s. d. 



Sperm Candles 8 



Gas (London) 13 



Oil (petroleum) .08 



Electricity, glow 9 



,, axe • • ■ • . • . • • .visr 



