758 ANNUAL KEPORT SMITHSONIAN INSTITUTION, 1908. 



attempts with bigger induction coils to get his apparatus to work. 

 After more than a week the reflecting galvanometer and ordinary 

 Daniell cells were resumed, and then clear messages were inter- 

 changed and international congratulations. News of peace with 

 China and of the end of the Indian mutiny was transmitted ; but the 

 insulation was found to be giving way, and on October 20, after 732 

 messages had been conveyed, the cable spoke no more. It had been 

 destroyed by Whitehouse's bungling use of induction coils, some 5 

 feet long, working at some 2,000 volts ! 



Of the part played by Thomson in the next eight 5^ears, in prepara- 

 tion for the cables of 1865 and 1866, there is not time to speak. 

 Suffice it to say that throughout the preparations, the preliminary 

 trials, the interrupted voyage of 1865, when 1,000 miles were lost, the 

 successful voyage of 1866, when the new cable was laid and the lost 

 one recovered from the ocean and completed, Thomson was the ruling 

 spirit whose advice was eagerly sought and followed. On his return 

 he was knighted for the part he played so well. He had in the mean- 

 time made further improvements in conjunction with Cromwell 

 Varley. In 1867 he patented the siphon recorder, and, in conjunc- 

 tion with Fleeming Jenkin, the curb transmitter. He was consulted 

 on practically every submarine-cable project from that time forth. 



Thomson's activities during the sixties were immense. Beside all 

 this telegraphic work he was incessant in research. He had under- 

 taken serious investigations on the conductivity of copper. He 

 was urging the application of improved systems of electric meas- 

 urement and the adoption of rational units. AVlien in 1861 Sir 

 Charles Bright and Mr. Latimer Clark proposed names for the prac- 

 tical units based on the centimeter-gxam-second absolute system. Sir 

 William Thomson gave a cordial support ; arid on his initiative was 

 formed the famous committee of electrical standards of the British 

 Association, which year by A^ear has done so much to carry to perfec- 

 tion the standards and the methods of electrical measurement. He 

 was largely responsible for the international adoption of the system 

 of units by his advocacy of them at the Paris congress in 1881 and in 

 subsequent congresses. He was an uncompromising advocate of the 

 metric system, and lost no opportunity of denouncing the " absurd, 

 ridiculous, time-wasting, brain-destroying British system of weights 

 and measures." His lecture in 1883 at the Civil Engineers may be 

 taken as a summary of his views, and it gives a glimpse of his mental 

 agility. So early as 1851 he had begim to use the absolute S3^stem, 

 stimulated thereto by the earlier work of Gauss and Weber. The 

 fact that terrestrial gravity varies at different regions of the earth's 

 surface by as much as half of 1 per cent compelled the use of absolute 

 methods where any greater accuracy than this is required. " For 



