EXPOSITION, PARIS. 



307 



The Electric Light. The Exposition offered 

 a favorable opportunity to M. Gramme and M. 

 Jablochkoff to bring into public notice their 

 systems of artificial illumination by electricity, 

 which was zealously utilized. Jablochkoff- 

 Gramme lamps, which were almost too daz- 

 zling for sight, although the light was tem- 

 pered by globes of ground glass, were placed 

 high above the heads of passengers in several 

 of the streets and places of Paris, and furnished 

 a light almost as clear as that of day, in which 

 all objects from the street below up to the tops 

 of the tallest houses were illuminated, and 

 everything was seen in its natural colors. The 

 American methods of electrical illumination 

 of Weston, Wallace, and Brush, were not on 

 exhibition; neither were the English devi- 

 ces shown. The Gramme machine, weighing 

 about 400 Ibs., and occupying about 4 cubic 

 feet of space, requiring 2-J- horse-power to 

 drive it, has an illuminating power of 5,700 

 candles. A new form of the Gramme machine 

 was shown, less durable in construction, which, 

 while weighing but 441 Ibs., and costing only 

 $300, has a power of illumination equal to 

 80,000 candles. While many parts of the city 

 were illuminated with the Jablochkoff electric 

 candle, in the Champ de Mars was a pavilion 

 specially devoted to the exhibition of this 

 light. In the first form of the Jablochkoff ap- 

 paratus, when the carbons were of equal size, 

 the one connected with the positive pole of 

 the electric machine was consumed twice as 

 rapidly as the other. This was remedied at 

 first by increasing the size of the positive car- 

 bon ; but in the apparatus exhibited it is cor- 

 rected by employing a rapidly alternating cur- 

 rent, instead of a continuous one, which method 

 possesses the advantage of keeping the carbon 

 points symmetrically tapered, producing a light 

 of perfect steadiness and equality. 



Metallurgy. The iron and steel exhibition 

 was far from being representative, as England 

 and America, the leading countries in these 

 branches, made very partial exhibits, while 

 Germany, which comes next, was absent, and 

 Belgium was represented, though ably, by but 

 a single firm. Russia, Austria, and Sweden 

 had, on the other hand, sent disproportion- 

 ately large and ambitious exhibits. The col- 

 lection of iron and steel products exhibited by 

 France was as full and varied as any ever 

 brought together, and showed that, although 

 the loss of Alsace and Lorraine deprived her 

 of a dozen of her largest iron works, she is 

 making vigorous efforts to keep abreast of the 

 world in these vital industries. The mining 

 products have, however, fallen off in France 

 since 1863, from three and a quarter to about 

 two million metrical tons ; but this is owing 

 to the progress made in the production of 

 Bessemer steel, which requires foreign ores. 

 The Schneider of Creusot, Terre-Noire, Besse- 

 ges, and St. Charaond companies exhibited in 

 separate pavilions. The great Creusot compa- 

 ny, which gives employment to 12,000 work- 



people, sent a wooden copy of their great steam 

 hammer, weighing 60 tons, with an anvil in 11 

 pieces of 720 tons weight; flie height of the 

 stroke is 5 metres ; the strength of the blow is 

 calculated to be equal to a shock of 412,500 

 kilos, while that of Krupp's 50-ton hammer is 

 only 150,000 kilos ; the cost of this great ham- 

 mer, standing 54 feet above the floor, with the 

 building in which it is worked, was about half 

 a million dollars. Among the exhibits of this 

 establishment, including shafting, sheets, gird- 

 ers, a puddling machine, fine marine and loco- 

 motive engines, armor-plates, etc., was a fac- 

 simile of a steel ingot weighing 113 tons. The 

 Terre-Noire works exhibited a series of steel 

 castings made with different admixtures of sili- 

 con and manganese, according to their famous 

 process. They are now able to produce, by 

 the employment of silicide of manganese and 

 iron, a malleable steel without blow-holes, 

 which, after annealing, possesses all the prop- 

 erties of forged steel ; their metal is somewhat 

 denser than rolled steel. They produce cast- 

 steel projectiles of remarkable penetrative pow- 

 er, and are experimenting on cannon in a sin- 

 gle piece which will have over three times the 

 power of resistance of the present steel guns 

 with a cast-iron body. With regard either to 

 strength or cheapness the Terre-Noire process 

 marks a great advance in metallurgical science. 

 Other noticeable improvements in steel manu- 

 facture are the Siemens-Martin-Pernot and the 

 Ponsard furnaces, which were exhibited by 

 their makers. At St. Chamond a Pernot ro- 

 tary furnace of as great as 20 tons capacity has 

 recently been put up, and a Martin furnace of 

 15 tons capacity at Terre-Noire, large furnaces 

 being found more economical. The Pernot 

 furnaces at St. Chamond, with Siemens's gaso- 

 gene, produced during three months an aver- 

 age of 20 tons of ingots per day, the furnaces 

 taking 7 tons to a charge and converting it in 

 about 7 hours. The Ponsard furnace is regen- 

 erative, and has the crucibles arranged in two 

 rows along its sides ; it is said to be simpler 

 and less expensive than the Siemens furnace, 

 which it resembles. There were some remark- 

 able ores exhibited in the main building, those 

 of the Champagne company containing 43 to 

 48 per cent, of metal. Fine chromium pig 

 metal and steel were shown by Holzer & Co. 

 from the Loire department, their best steel be- 

 ing made from spathic ore found at Ria in the 

 Pyrenees. There were specimens of manufac- 

 tured iron, T-bars, cables, wire, rounds, and 

 squares, from different furnaces, which equaled 

 the best English products. The Compagnie 

 de 1'Horme of St. Chamond showed a new pro- 

 cess of tempering malleable iron in sulphuric 

 acid, which is said to increase its power of 

 tension 30 per cent. The models and draw- 

 ings of the works in the difficult and irregular 

 ore and coal beds of France gave evidence that 

 that country excels all the rest of the world in 

 mining arrangements and facilities. 

 In the English exhibit there were specimens 



