WATSON'S ELECTRICAL CIRCUIT. 549 



Lemonnier had apparently caused electricity to traverse 

 the pond in the Tuileries gardens. This Watson deter- 

 mined to outdo; and, not without some misgivings, pre- 

 pared to make the "commotion," as he calls it, felt across 

 the River Thames. With the aid of several members of the 

 Royal Society he laid a wire along Westminster Bridge a 

 distance of some twelve hundred feet and carried its ends 

 to the water edge. On the Westminster side of the river 

 one of the company held the wife in his left hand and 

 touched the water with an iron rod held in his right. On 

 the Surrey side, a second person held the extremity of the 

 wire in his right hand and a charged Leyden jar in his left 

 the ball of the jar being touched by a third observer, 

 who also grasped an iron rod dipping into the river. All 

 three individuals felt a smart shock the instant the circuit 

 was closed, and alcohol on one bank of the stream was 

 fired by electricity discharged on the other. 



This experiment, which was repeated with various 

 changes in detail, was made in July, 1747. Martin Folkes, 

 then president of the Royal Society, the Earl of Stanhope, 

 and other distinguished persons, took part in it ; and 

 this alone would have attracted public attention even if 

 the results had not been of such great philosophical inter- 

 est. Watson, however, cared nothing for the sensational 

 or popular side of the achievement. The observation 

 which seemed to him of most importance was the great 

 advantage which wire, as a conductor, possesses over chain 

 for "the junctures of the chain not being sufficiently 

 close . . . caused the electricity in its passage to snap and 

 flash at the junctures where there was the least separation, 

 and these lesser snappings in the whole length of the 

 chain lessened the great one at the gun barrel," which 

 formed a terminus of the line. This suggested to him 

 the possibility of sending the discharge over circuits of 

 wire and water even greater than 2400 feet in length; 

 so he changed the scene of his operations to Stoke-New- 

 ington, where the windings of the New River gave him 



