THE TELEGRAPH COMMISSION. 57 



improvement to be expected therein. In consequence 

 of this I was ordered to place myself at the service of 

 the commission of the staff, which was deliberating on 

 the introduction of electrical instead of optical tele- 

 graphs. I succeeded in gaining the confidence of the 

 general and his son-in-law, professor Dove, in so high 

 a degree, that the commission almost always assented 

 to my proposals and entrusted me with their execution. 

 It was then regarded as altogether out of the 

 question that a telegraph wire easy of access, attached 

 to posts, could be really serviceable, since it was 

 imagined the public would destroy it. Accordingly, 

 wherever on the European continent it was desired 

 to introduce electric telegraphs, experiments were first 

 made with subterranean conductors. The best known 

 were those of Professor Jacobi in St. Petersburg: he 

 had tried resin, glass-tubes, and india-rubber as in- 

 sulators, but had obtained no permanently satisfactory 



results. The Berlin commission likewise had begun 



t? 



such experiments, which however just as little yielded 

 a satisfactory durable insulation. 



By chance my brother William in London had 

 sent me as curiosity a sample of a substance which 

 had recently appeared in the English market, gutta- 

 percha. The remarkable properties of this material 

 of becoming plastic 'in the heated state, and when 

 cooled of being a good insulator of electricity, aroused 

 my attention. I covered some pieces of wire with the 

 heated material, and found that they were thoroughly 

 insulated. At my suggestion the commission gave 



