MR W. H. PREECE ON ELECTRICITY.

Hawke's Bay Herald, Volume XXIV, Issue 8332, 8 April 1889, Page 3

MR W. H. PREECE ON ELECTRICITY.

(Chicago Globe.)

" Five million people upon the face of the globe are now dependent on the electric current for their daily bread." So said the veteran English electrician, W. H. Preece, in concluding his address on "Electric Inventions" at the recent ineetin . of the British Association of Science. In the course of his remarks he

mentioned many employments to which electricity is put, many recent economies in evolving and distributing the agent, many arts that depend entirely thereon. All onr readers are familiar with the telegraph, many of tbem with the telephone, and all city people with the electric light. But few have any notion of the rapid improvement of processus in these services, of the multitudinous work in which the above-mentioned live million peoplo are engaged, or of the uses to which tlie mysterious current is likely to he put in the near future. Mr Preece said :— " Scarcely a week passes without some fresh application of its principles, and we seem to be only on the shore of that sea of economy and beneficence whicli expands witli every discovery of tlie properties of electricity." Some enthusiasts allege tbat objects in one country may yet be rendered visible to the naked eye by electricity to the people of another. MrJP reece calls this a dream, but admits, in face of the wonders that have been done, no one dare say that it is impossible. But he devoted most of his address to recerding, not the astounding hopes or fancies of electricians, but their achievements. The Government telegraph service of Great Britain transmits, on the average, 1,538,270 words per day to newspapers alone. On April 8, 1886, when Mr Gladstone introduced bis Home Rule Bill, 1,500,000 words were sent from the Central telegraph office of London. On the day of the nomination of Harrison and Mortonsoo,ooo\vords were sent from Chicago, a feat much boasted of by Americans. The first needle instrument of Cook and Wheatstone required live wires for tbe transmission of four words a minute. One wire now conveys six messages at four times the speed. The first Morse apparatus sent five words a minute, whereas 600 words a minute are now transmitted by one machine. Only thirteen years ago it was thought wonilerful that eighty-five words a minute ::ould be sent by cable to Ireland. Mr Preece recently timed messages coming to Belfast from England at the rate of 461 words per minute. British ships have laid down 110,000 miles of ocean cable, at a cost of £40,000,000 of private capital, to say nothing of Government subsidies. Thirtyseven British ships are constantly engaged iv laying new cables or making repairs to tbe old. . The safety of railway travelling in Lagland has been so promoted by tne recent application of telegraphy that only 16 people are killed by railway accidents in a year, whereas 35 were killed annually a few years ago on much less line. The iirst telephone was exhibited only 11 years ago. Tliere are at least a million telephones now in use throughout the world. Conversation is now carried on over a circuit of 600 miles between Paris and Marseilles.

Tlie influence of electric currents on neighboring wires extends to enormous distances, and communication between trains or ships in motion, or between islands and the mainland, has become possible without the aid of any wires by induction through the air itself. Ou the American Lehigh Valley road such a system of telegraphy without wires is in daily use. The electric light has proved to be not merely a more brilliant and steady illuminant than any other that can be cheaply produced, but cooler, better for the eyes, and in all respects more healthful. It throws off neither poisonous fumes nor dirt. Two years' use of it in the Postoffice Central Savings Bank in London remarkably diminished absences of the staff from illness, and saved £266 a year on the cost of lighting. In six years the cost of supplying the Edison light has been diminished by more than 50 per cent. Mr Preece finds, by careful cxi periment, that the cost of production of one-candle ligbt per 1000 hours is as follows :— Sperm candles, 8s 6d ; gas, ls 3d ; petroleum, 8d ; electricity (Edison), 9d ; electricity (arc), l^d. Nearly all the British war-ships have been fitted with the electric light. All first-rate commercial steamships use it. So do many English express trains. It is being suppUed as rapidly as possible to British lighthouses, and will no doubt, soon become the common domestic illuminantot the civilised world. Mr] Preece points" out that twenty-four thousand "glow" or Edison lamps are operated ou the "secondary generator principile "— a system which is likely to be soon so improved that boxes of stored electricity may be delivered anywhere and tapped and used as easily as a keg of syrup. " The discovery of the reversibility oi the dynamo bas," said Mr Preece, " brought the waste forces of nature within our reach. The waterfalls of _Vales may be utilised in London ; the torrents of the Highlands may work the tramways of Edinburgh ; the wasted horse-power of Niagara may light up New York." He mentions a number ol instances of machinery werked in England by transmission of electricity from distant points. Such transmission over long distances is, however, at present so costly as to be impracticable for general purposes. But motors for small industries can be and are supplied advantageously with electricity transmitted from central stations. Mr Preece believes that electric rail-

ways will before very long supplant other methods of land transport. The electrical current bas^ revolutionised a number of old . idustries and created many new ones. For instance, tliere are 172 electroplaters in Sheffield and 99 in London. Nickel-plating hy electricity is becoming a very great industry. The purification of copper by tbe current, first undertaken in 1871, has been so beneficial that whereas "it was not very long ago considered very economical to absorb -85 horse-power in depositing lib of copper per hour, the same work can now be done with -3 horse-power. . . : Copper steampipes for boilers are now being built up of great firmness, fine texture, and considerable strength by .electro deposition ou n rotating mandrel in a tank of sulphate of copper"' Electricity is very largely employed in separating gold, silver, and other metals from the constituents of their ores. The late Sir W. Siemens, immediately before his death, was engaged in experimenting with the electric 1 w to. fuse mstala w_t . igU welting

points. He had succeeded in melting ninety-six ounces of platinum in ten minutes. His process is now being employed in producing aluminum. Large concerns in "Russia and the United States use the electric are to Weld

metals, and it is proposed "to weld together in one continuous mass the rails of our railways so as to dispense entirely with joints." The electric current is employed in producing chlorine and iodine, in running clocks which need no winding, and in distributing correct mean time instantaneously from Greenwich and other observatories. Mr Preece said :—

" Warehouses and shops are fitted with automatic contact-pieces,' which on any undue increase of temperature due to fire create an alarm in the nearest fire station, and at the corner of most streets a post.is found with a face of glass, which on being broken enables the passer-by or the watchful and active policeman to call a liie engine to the exact spot of danger, in- sewers are likely to find in its active chemical agency a power to neutralise offensive gases, and to purify poisonous and dangerous fluids. The germs of disease are attacked and destroyed in their very lairs. The physician and the surgeon trust to it to alleviate pain, to cure disease, to effect organic changes beyond the reach of drugs. The photographer finds in the brilliant rays of the arc lamp a miniature sun which enables him to pursue his lucrative business at night, or during the dark and dismal hours of a black November fog in London.

it is proposed (in New York Stale) to replace hanging by the more painless and sudden application of a powerful electric charge, but those who have assisted at this hasty legislation would have done well to have assured themselves of the practical efficacy of the proposed process. I have seen the difficulty of killing even a rabbit with the most powerful induction coil ever made, and I know those who have escaped and recovered from the stroke of a lightning discharge. Electricity for many civil, military, and naval purposes has become an invaluable and essential agent. Wrecks like that of the Koyal George at Spithead wefe blown up apd destroyed ; the faces of cliffs and quarries are thrown down ; the galleries of mines and tunnels are excavated ; obstructions to navigagation, like the famous Hell Gate near New York, have been removed ; time guns to distribute correct time are fired from Greenwich at 1 p.m. In the operations of war, both for attack and defence, submarine mining has become the most important branch of the profession of a soldier and a sailor. Big guns, whether singly or in broadside, aie fired, and torpedoes, when au enemy's ship unwittingly is placed over them, are exploded by currents of electricity." We have mentioned but few of the uses to which electricity is already put. Those to which it is likely to be applied are innumerable. The science and art of electricity are still in their infancy, and already the imagination staggers at the prediction of sober-minded experts as to the extent of the applicability of the agent.