Stdt VitMT 

 F I c 2 



ria?i in, Stetu/n. 

 F I C . I . 



Figure 32. — Patent drawing of Millward's 



magneto generator, 1851. From British 



patent specification 13536, February 28, 

 1851. 



were redesigned for the production of alternating- 

 current: one end of the coils on each armature was 

 connected to the axis and the other was connected to 

 an insulated sleeve on it (fig. 41 ) . It was found that a 

 greater amount of current was produced if the re- 

 sistance of the coils were reduced by winding more 

 turns in parallel on each of the 16 spools on the 

 armature. Preliminary results from the new design 

 were so encouraging that the first 5-disk machine 

 constructed since 1856 was demonstrated at the Hotel 

 des Invalides in the early spring of 1859.^^ Unlike 

 Holmes' constant experimentation, no further changes 

 in the design of the Alliance machine were made. 

 The only modifications were in the number of disks 

 in the machine, with six seeming to have been the 

 largest practical number on a single arbor, although 

 Jamin and Roger apparently used a 9-disk nnachii.e 

 in 1868. 



'8 Bulletin de la Societe d' Encouragement pour ['Industrie Mationale, 

 1859, vol. 6, p. 189; Du Moncel, op. cit. (footnote 5), vol. 4, 

 pp. 39^7; vol. 5, pp. 102-104. 



« Cosmos, 1860, vol. 17, p. 427. 



^Annates telegraphiques, 1861, vol. 4, p. 84; 1862, vol. 5, 

 pp. 505-520; Bulletin de la Societe pour V Encouragement de P Industrie 

 Rationale, 1861, vol. 8, pp. 181-182: Cosmos, 1861, vol. 



The Societe I'Alliance was sufficiently confident of 

 its redesigned machine to consider public demon- 

 strations, and Berlioz was very energetic in seeing 

 that proper occasions were found. In the late fall of 

 1860 a combination of the Serrin regulator and the 

 Alliance machine was tried on the Dauphin's steam 

 frigate,*' and it proved successful "in spite of the size 

 of the equipment." In the spring of 1861 two 6- 

 disk machines driven by a 4-hp. steam engine were 

 used for public illumination of the Arc de Triomphe 

 at the Place du Carrousel: other demonstrations were 

 carried out at the Place du Palais Royal early in the 

 summer, and civil authorities tested but rejected the 

 light for street illumination.^" In the following year 

 a 4-disk machine shown at the London Exhibition of 

 1862 produced an arc light of 125 Carcel units mean 

 intensity when driven by a l^-hp. steam engine at 

 300 r.p.m. The Societe I'Alliance was awarded a 

 medal for that performance.^' 



When combined with the Serrin arc light (fig. 42), 

 the new Alliance generator proved it could produce 



18, pp. 197-200; vol. 19, p. 29; V Illustration, 1861, vol. 37, p. 

 347; L'Annee scientifique, 1862, vol. 6, pp. 48-52. 



51 Dinglers polytechnisches Journal, 1863, vol. 167, pp. 104-111; 

 Cosmos, 1862, vol. 20, pp. 686-694; Daniel K. Clark, The 

 Exhibited Machinery oj 1862, London, 1864, pp. 288-289. 



P.A.PER 30: DEVELOPMENT OF ELECTRIC.A.L TECHNOLOGY IN THE 19TH CENTURY: III 



357 



