1902.] on the Progress of Electric Space Telegraphy. 209 



land, where I should have probably been landed into litigation with 

 the telegraph company. I am glad to say that the Canadian Govern- 

 ment, on the initiative of Sir Wilfred Laurier and Mr. Fielding, has 

 shown itself most enterprising in the matter, and not only encouraged 

 the erection of a large station in Nova Scotia, but actually granted a 

 subsidy of 16,000Z. towards the erection of this trans-Atlantic station, 

 the object of which is to communicate with England from the coast 

 of Nova Scotia. It is anticipated that the Canadian station will be 

 ready for further tests very shortly. Another station for tlie same 

 purpose is being erected on the United States coast. 



Towards the end of February of this year I thought it desirable 

 to test how far the messages transmitted by the powerful station at 

 Poldhu could be detected on board a ship. The ship selected was 

 the " Philadelphia," of the American line. The receiving aerial con- 

 ductor was fixed to the mast, the top of which was about 60 metres 

 above sea level. As the elevated conductor was tised, and not float- 

 ing about with a kite, as in the case of the Newfoundland experi- 

 ments, very good results were obtained on an ordinary syntonic 

 receiver, similar to those I have already described, and the signals 

 were all recorded on tape by the ordinary Morse recorder. Keadable 

 messages on tape were received up to a distance of 1551 miles from 

 Cornwall, and indications were received as far as 2099 miles. Most 

 of the messages were received in the presence of the captain or the 

 chief officer of the ship, who were good enough to sign the tapes. I 

 have some of these tapes here, in a frame, and they can be examined 

 at the conclusion of my discourse. It is curious to observe that 

 signals could not be received at over 900 miles by any of the self- 

 restoring coherers. The reason for this lies probably in the fact that 

 the tuned receiver, when connected to a fixed aerial is moj-e efficient. 

 Another result of considerable scientific interest was that at distances 

 of over 700 miles the signals transmitted during the day failed 

 entirely, while those sent at night remained, as I have stated, quite 

 strong up to 1551 miles, and were even decipherable up to a distance 

 of 2099 miles. This result, which I had the honour of describing 

 ^ before the Royal Society yesterday afternoon, may be due to the dis- 

 electrification of the very highly charged transmitting elevated 

 conductor operated by the influence of daylight. 



I regret time does not permit me to give vou the views which have 

 been expressed with reference to this phenomenon. I do not think, 

 however, that the effect of daylight will be to confine the working of 

 trans-Atlantic wireless telegraphy to the hours of darkness, as sufficient 

 sending energy can be used during day-time, at the transmitting station, 

 to make up for the loss of range of the signals, and therefore this 

 business of communicating across the Atlantic will not be one of those 

 works of darkness with which some people connected with cable 

 companies would seem disposed to class it. It is, however, probable 

 that had I known of this effect of light at the time of the Newfound- 

 land experiments, and had tried receiving at night-time, the results 

 would have been much better than those that were obtained. 



Vol. XVII. (No. 96.) p 



