1902.] on the Progress of Electric Space Telegraphy. 207 



about a certain slight change of appearance in the rig of the ships. 

 Some naval officers believe that this change improves the ships' 

 appearance ; others think the contrary. 



The Italian Admiralty, after experimenting for some time with 

 the self-decohering coherers to which I have referred before, have 

 informed me officially, by a letter dated May 24th last, of its decision 

 to equip their war vessels with the same apparatus as has been 

 successfully employed on the transatlantic liners. On these liners 

 commercial use is made of the system for the convenience of passen- 

 gers, and as an illustration of its commercial workableness T might 

 mention that lately the " Campania " and " Lucania " of the Cunard 

 line have been collecting as much as 60Z. each trip in receipts derived 

 from passengers' wireless messages. 



Nearly two years ago the facility with which communication was 

 possible over distances of nearly 200 miles, and the improvements in 

 syntonic methods introduced, together with the ascertained fact of 

 the non-interference of the curvature of the earth, led me to decide 

 to recommend the construction of a large power station in Cornwall 

 and another one at Cape Cod, Mass., U.S.A., in order to test whether, 

 by the employment of much greater power, it might not be possible 

 to transmit messages across the Atlantic, and establish a trans- 

 oceanic commercial communication which the monopoly of the Post- 

 master-General will not apparently permit between two stations if 

 both are situated in Great Britain. An unfortunate accident to the 

 masts at Cape Cod seemed likely to postpone the experiments for 

 several months, when I came to the conclusion that while the neces- 

 sary repairs there were being carried out I would use a purely tem- 

 porary installation in Newfoundland for the purpose of a trans- 

 Atlantic experiment, from which I might, at any rate, be able to judge 

 how far the arrangements in Cornwall had been conducted on right 

 lines. Before describing the results it may b6 useful if I give a brief 

 description of the nature of the apparatus used at the transmitting 

 and receiving stations. 



The transmitter at Poldhu was similar in principle to the syntonic 

 one I have already described, but the elevated conductor at the 

 transmitting station was much larger, and the potential to which it 

 was charged very much in excess of any that had previously been 

 employed, the amount of energy to be used in this transmitting 

 station having been approximately determined by me prior to its 

 erection. The transmitting elevated conductor consisted of 50 almost 

 vertical naked copper wires, suspended at the top by a horizontal 

 wire stretched between two poles, each 48 metres high, and placed 

 60 metres apart. These wires were separated from each other by a 

 space of about 1 metre at the top, and, after converging together, 

 were all connected to the transmitting instruments at the bottom. 

 The potential to which these conductors were charged during trans- 

 mission was sufficient to cause sparking between the top of the said 

 wires and an earthed conductor across a space of 30 cm. of air. The 

 general engineering arrangements of the electric power station erected 



