Figure 33. — On facing page and above: Patent drawings of Holmes' magneto generator of 1856. 

 Note the current collectors and the speed regulator on the machine. From British patent 

 specification 573, March 7. 1856. 



he recommended that the g-overnment purchase a 

 pair of Alliance machines for actual trial in a light- 

 house of the first-order. ^- 



52 L' Illustration, 1863, vol. 42, p. 190; J. H. Gladstone, "Light- 

 house Illumination by Magneto-Electricity," Quarterly Journal 

 of Scierue, 1864, vol. 1, pp. 70-75; Cosmos, 1859, vol. 15, pp. 

 511-512; Faye, "De 1' Application des feux electriques aux 

 phares et a Tillumination a longue portee," Comptes rendus, 

 1861, vol. 52, pp. 375-377, 413-415; Leonce Reynaud, "Rap- 

 port sur I'application de la lumiere electrique a Teclairage des 

 phares," Bulletin de la Societe d' Encouragement pour I'Industrie 

 Nationale, 1863, ser. 2, vol. 10, pp. 496-504. Fontaine {op. 

 cit., footnote 12, p. 352) gives one Carcel unit as 7.4 English 

 candles, and other values of the period ranged between 7.5 

 and 9.5 candles. The current value of the Carcel uniti s 9.6 

 English standard candles {Smithsonian Physical Tables, Washing- 

 ton, 1954, rev. ed. 9, p. 92). 



I n a short time the Alliance-Serrin combination began 

 to appear in some of the lighthouses along the coast 

 of France. Following Reynaud's report, on July 14, 

 1863, two 6-disk machines were ordered for Cap de la 

 Heve near the port of Le Havre (figs. 43-45).'^ They 

 had the usual combination of 16 electromagnets in 

 each disk and eight permanent magnets in each of the 

 seven banks of magnets. When the machine was 

 driven by a 2-hp. steam engine at 400 r.p.m. the 

 engineers found that about 190 Carcel units were 

 produced in the arc. The south lighthouse on the cape 



=3 Les Mondes, 1863, vol. 1, pp. 691-694; Cosmos, 1863, vol. 23, 

 p. 115; V Illustration, 1863, vol. 42, p. 190; L'Annee scientijique, 

 1864, vol. 8, pp. 63-74. 



PAPER 30: DEVELOPMENT OF ELECTRICAL TECHNOLOGY IN THE 19TH CENTURY: III 



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