Jan. 22, 1880] 



NATURE 



283 



The cry for more light having been raised in 

 consequence of the experiments conducted with elec- 

 tricity, a new gas burner has been invented by the 

 Compagnie Parisienne, and placed experimentally in 

 several large public thoroughfares, principally the Rue du 

 4 Septembre, the Place de la Republique, formerly place du 

 Chateau d'Eau, and a pavilion in the Halles Centrales. 

 The burners used in the Rue du 4 Septembre are the 

 largest, and all the new burners have been constructed on 

 the same principle. The ordinary- wing burners consume 

 about 120 litres of gas each hour. In these improved 

 lanterns six burners, representing an hourly consumption 

 of 1,400 litres, have been placed at the six summits of a 

 hexagon. In the centre is a hole for facilitating the 

 introduction of air and better consumption. The effect is 

 really highly satisfactory, and the luminous effect is far 

 greater than in proportion to the gas consumed. A 

 large number of coffee-houses, theatres, and first-class 

 shops have adopted the burners for exterior use. It is 

 impossible to use them within any building except 

 markets, owing to the immense quantity of heat radiated, 

 which would be a nuisance, at least in summer time. A 

 number of these improved gas lamps have been placed in 

 the Lyons railway station (passenger department), and 

 will be, within a few days, used for competitive experi- 

 ments with the Lontin electric light. 



Besides the hole for admission of air, a gas-pipe is 

 placed in the central part of the lamp. The aperture has 

 been disposed so that a small jet is always burning, and 

 thus for lighting the lamp it is sufficient to open the valve 

 of the gas pipe, and the six peripheral burners are lighted 

 at once. After midnight the jets are extinguished and 

 the central one opened, burning with a consumption of 

 120 litres per hour, or like an ordinary old gas-burner. 

 The supplementary gas consumed by the city is paid for at 

 a very cheap rate, about is. 6if. per thousand cubic feet. It 

 must be said, moreover, that the Chambre Syndicale des 

 Tissus and other commercial institutions have organised 

 an agitation to oblige the Municipal Corporation to 

 diminish the price of the gas. The Commission of the 

 Municipal Council is at present deliberating upon that 

 important question. A large factory, the Say Sugar 

 Refinery, close to the Orleans Railway Station, built a 

 private gas-work for its own use. They consume yearly 

 about 6,000,000 cubic feet, and will turn their own gas- 

 makers. 



In electrical lighting the division principle is repre- 

 sented in Paris by the celebrated Jablochkoff candle, and 

 a diversity of opinions have been expressed on the subject. 

 The apparatus in itself requires no description, but it is 

 necessary to explain the results which have been obtained. 



The Jablochkoff light, placed in an opal globe is consi- 

 dered as perfectly suited to large shops and large public 

 thoroughfares, although the diminution of light by the 

 interposition of the globe may be valued at 45 per cent. 

 The price of effective light is enlarged in the same pro- 

 portion. This is the reason why many persons suppose that 

 from an economical point of view it will never do except 

 in large open places, as the Place de la Bastille, where 

 semi-transparent globes are used without fear of any com- 

 plaints from shopmen or street passengers. But even for 

 illuminating these large places, it is supposed by many 

 competent persons that other electric lights would be 

 more successful, and at all events more economical. 

 The only place where the Jablochkoff candles can 

 be considered as unrivalled are large establishments 

 like the Grands Magasins du Louvre, the Buttes 

 Chaumont and the Ville de France, where the effect 

 obtained is alone considered without much regard to the 

 expense. The illumination of the Palais de l'Industrie 

 during the evening sittings of the Exhibition of Fine Arts, 

 was a success last summer. It was not attempted a second 

 time during the Exhibition of Sciences Applied to 

 Industry, owing to several circumstances, having nothing 



to do with the value of the system. At the Hippodrome 

 the illumination is effected by a combination of gas lights 

 and Jablochkoff candles, and ordinary regulators with 

 luminous points carefully concealed. The general effect 

 is quite satisfactory, but the expense in motive power is 

 considerable. 



Jablochkoff candles are used in the illumination of 

 large works carried on at present on the Seine for re- 

 pairing the Pont des Invalides. These works have been 

 interrupted for the last month owing to the frosty 

 weather, but the Jablochkoff light has worked admirably. 

 The me of the Jablochkoff candles is progressing im- 

 mensely in private establishments, although the Municipal 

 Council will in all probability discontinue the electric 

 lighting of the Avenue de I'Opera, the Place de la 

 Bastille, &c, from February 1, and keep it burning 

 only on the Place de l'Opera. This impending resolution 

 is attributed to the prevalence of the gas interest. 



In the first months of the Jablochkoff trial, many com- 

 plaints w-ere made against the irregularities of the light ; 

 now extinctions are almost unknown, and the red colour 

 of the electric flame less frequent. 



Extensive preparations have been made in the green 

 room of the opera for a comparison between Jablochkoff 

 and Werdermann candles, and will be completed in a few 

 weeks. It is argued by YVerdermann's opponents that his 

 light is merely incandescent light, and that the loss of 

 illuminating power is far greater than with the Jablochkoff 

 system. M. Gamier, the architect, being intrusted with the 

 task of reporting on the matter, it would be unbecoming to 

 give an opinion before his verdict is published. M. Reynier 

 has another incandescent light offering some analogy 

 with Werdermann's, but the contact being more intimate, 

 the loss in power is larger, and the public exhibition of it 

 has been considered a failure. It is regarded as merely 

 an apparatus for lecturers wishing to show their audience 

 an electric light with few elements. The lamp is cheap, 

 and its working quite regular. 



It should not be forgotten that even naked Jablochkoff 

 lights lose a part [of their illuminating power. A quan- 

 tity of electricity, which may be valued at 30 per cent., 

 passes through the insulating caolin or plaster. 1 Conse- 

 quently it must not be wondered at, if some inventors 

 tried to dispense with insulating lamina. 



M. Denayrouze, the former lessee of the Jablochkoff 

 candle, has purchased the Jamin candle, in which the 

 electric flame is directed by the attractive power of 

 magnetism or electricity. Private experiments have been 

 made, and they are preparing for an exhibition in one of 

 the suburbs of Paris. M. Jamin having to lecture at the 

 Sorbonne on January 17 it is probable that the large hall 

 will be illuminated by his own light on this occasion. 

 This light company has purchased a patent for gas 

 engines, and will try to use the gas under the furnace as 

 fuel, dispensing with it for illumination. They are said 

 to contemplate a public issue of shares for a large capital. 



It is known that the principal difficulties in the con- 

 struction of regulators, has always been the absolute 

 fixity of the luminous point in space. It has led M. 

 Serrin to the invention of his excellent regulator. But the 

 use of the Jablochkoff light proved that inventors had 

 gone too far in the way of complication, at least for 

 street illumination, and where no dioptric or catoptric 

 arrangement is contemplated. M. Suisse was the first to 

 start a lamp which may be regarded as a simplification of 

 Serrin's original, and is working very well. The carbon 

 is placed upwards, and descends in proportion as the 

 negative is consumed. In order to diminish that con- 

 sumption the diameter of the negative carbon has been 

 enlarged. . 



A number of regulators have been tried in competition. 



■ It shows that a Jablcchkoff candle placed in an opaque globe is diniiii- 

 ished (,) 070 by .he loss of the caohn. and (2 050 by the opac.ty of the 

 globe, so that it gives only 035 of the or.gtnal tlluminaung power. 



