February 15, 1900] 



NA TURE 



379 



40 miles before she lost touch while steaming ahead at a fast 

 speed. (This difference between the ranges of communication 

 n these ships was owing to ihejittio having a higher mast than 

 ; lie Ale.raniira). 



" Reaching the convoy at four o'clock one afternoon, and 

 leaving it and the several cruisers in charge of the senior 

 captain, the Europa hastened back towards another rendez- 

 vous, where the Admiral had intended remaining until he 

 sliould hear whether the enemy had found and captured the 

 convoy ; but scarcely had she got well ahead of the slow ships 

 when the Jitiio called her up and announced the Admiral 

 coming to meet the convoy. The Juno was at this lime fully 

 60 miles distant from the Europa. 



"Now imagine," says Commander Statham, "a chain of 

 vessels 60 miles apart. Only five would be necessary to com- 

 municate some vital piece of intelligence a distance of 300 

 miles, receive in return their instructions, and act immediately 

 all in the course of half an hour or less. This is possible 

 already. Doubtless a vast deal more will be done in a year or 

 two or less, and meanwhile the authorities should be making 

 all necessary arrangements for the universal application of 

 wireless telegraphy in the navy." 



The most important results, from a technical point of view, 

 obtained during the manct'uvres were the proof of the great 

 increase of distance obtainable by employing the transformer 

 in the receiver, as already explained, and also that the 

 curvature of the earth which intervened, however great the 

 distance attained, was apparently no obstacle to the trans- 

 mission. The maximum height of the top of the wire attached 

 to the instruments above the water did not on any occasion 

 exceed 170 feet, but it would have been geometrically necessary 

 ) have had masts 700 feet high on each ship in order that a 

 :raight line between their tops should clear the curved surface 

 if the sea when the ships were 60 nautical miles apart. This 

 shows that the Hertzian waves had either to go over or round 

 the dome of water 530 feet higher than the tops of the masts 

 or to pass through it, which latter course I believe would be 

 impossible. 



Some time after the naval manceuvres, with a view to showing 

 the feasibility of communicating over considerable distances on 

 land, it was decided to erect two stations, one at Chelmsford 

 and another at Harwich, the distance between them being 40 

 miles. These installations have been working regularly since 

 last September, and my experiments and improvements are 

 continually being carried out at Chelmsford, Harwich, Alum 

 Hay, and North Haven, Poole. 



In the month of September last, during the meetings of the 

 British Association in Dover and of the Association Fran^aise 

 pour I'avancement de Science in Boulogne, a temporary instal- 

 lation was fixed in the Dover Town Hall, in order that members 

 present should see the practical working of the system between 

 Kngland and France. Messages were exchanged with ease be- 

 tween Wimereux, near Boulogne, and Dover Town Hall. In 

 this way it was possible for the members of the two associa- 

 tions to converse across the Channel, over a distance of 30 

 miles. 



During Prof. Fleming's lecture on the "Centenary of the 

 Klectric Current," messages were transmitted direct to and re- 

 ceived from P'rance,and vid the .South Foreland Lighthouse to the 

 East Goodwin Lightship. An interesting point was that it was 

 demonsi rated that the great masses of the Castle Rock and 

 South Foreland cliffs lying between the Town Hall, Dover, and 

 the lighthouse did not in the least degree interfere with the 

 transmission of signals. This result was, however, by no means 

 "new. It only confirmed the results of many previous experi- 

 "ments, all of them showing that rock masses of very considerable 

 size intervening between' two stations do not in the least affect 

 ^he freedom of communication'by ether wave telegraphy. (.See 

 /oiirnal ol the Institution of Electrical Engineers, April 1899, 

 p. 280.) 



It was during these tests that it was found possible to 

 communicate direct from Wimereux to Harwich or Chelmsford, 

 the intervening distance being 85 miles. This result was pub- 

 lished in a letter from Prof, l^leming addressed to the Elec- 

 trician on September 29. The distance from Wimereux to 

 Harwich is approximately 85 miles, and from Wimereux to 

 Chelmsford also 85 miles, of which 30 miles are over sea and 

 55 over land. The height of the poles at these stations was 

 150 feet, but if it had been necessary for a line drawn between 

 the tops of the masts to clear the curvature of the earth they 



NO. 1581, VOL. 6lj 



would have had to have been over 1000 feet high. I give these 

 results to show what satisfactory pr,ogress is being made with 

 this system. 



In America wireless telegraphy was used to report from the 

 high seas the progress of the yachts in the International Yacht 

 Race, and I think that occasion holds the record for work done 

 in a given time, over four thousand words being transmitted in 

 the space of less than five hours on several different days. 



Some tests were carried out for the United States Navy ; but, 

 owing to insufficient apparatus, and to the fact that all the 

 latest improvements had not been protected in the United 

 States at that time, it was impossible to give the authorities 

 there such a complete demonstration as was given to the British 

 authorities during the naval mancjeuvres. Messages were trans- 

 mitted between the battleship Massachusetts and the cruiser 

 NiW York up to a distance of 36 miles. 



A few days previous to my departure from America the war 

 in South Africa broke out. Some of the officials of the American 

 line suggested that, as a permanent installation existed at the 

 Needles, Isle of Wight, it would be a great thing, if possible, to 

 obtain the latest war news before our arrival on the .SV. Paul2X 

 Southampton. I readily consented to fit up my instruments on 

 the St. Paul, and succeeded in calling up the Needles station 

 at a distance of 66 nautical miles. By means of wireless 

 telegraphy, all the important news was transmitted to the 

 St. Paul while she was under way, steaming twenty knots, and 

 messages were despatched to several places by passengers 

 on board. News was collected and printed in a small paper 

 called the Transatlantic Times several hours before our arrival 

 at Southampton. 



This was, I believe, the first instance of the passengers of a 

 steamer receiving news while several miles from land, and seem.s 

 to point to a not far distant prospect of passengers maintaining 

 direct and regular communication with the land they are leaving 

 and with the land they are approaching, by means of wireless 

 telegraphy. 



At the tardy request of the War Office, we sent out Mr. 

 Bullocke and five of our assistants to South Africa. It was the 

 intention of the War Office that the wireless telegraph should 

 only be used at the ba.se and on the railways, but the officers on 

 the spot realised that it could only be of any practical use at the 

 front. They therefore asked Mr. Bullocke whether he was 

 willing to go to the front. As the whole of the assistants 

 volunteered to go anywhere with Mr. Bullocke, their services 

 were accepted, and on December 11 they moved up to the 

 camp at De Aar. But when they arrived at De Aar, they found 

 that no arrangements had been made to supply poles, kites, or 

 balloons, which, as you all know, are an essential part of the 

 apparatus, and none could be obtained on the spot. To get 

 over the difficulty, they manufactured some kites, and in this 

 they had the hearty assistance of two officers, viz. Major Baden- 

 Powell and Captain Kennedy, R.E., who have often helped me 

 in my experiments in England. (Major Baden- Powell, it will 

 be remembered, is a brother of the gallant defender of 

 Mafeking. ) 



The results which they obtained were not at first altogether 

 satisfactory, but this is accounted for by the fact that the work- 

 ing was attempted without poles or proper kites, and afterwards 

 with poles of insufficient height, while the use of the kites was 

 very difficult, the kites being manufactured on the spot with 

 very deficient material. The wind being so variable, it often 

 happened that when a kite was flying at one station there was 

 not enough wind to fly a kite at the other .station with which 

 they were attempting to communicate. It is therefore manifest 

 that their partial failure was due to the lack of proper pre- 

 paration on the part of the local military authorities, and has 

 no bearing on the practicability and utility of the system when 

 carried out under normal conditions. 



It was reported that the difficulty of getting through from one 

 station to another was due to the iron in the hills. If this had 

 not been cabled from South Africa, it would hardly be credible 

 that any one should have committed himself to such a very 

 unscientific opinion. As a matter of fact, iron would have no 

 greater destructive effect on these Hertzian waves than any 

 other metal, the rays apparently getting very easily round or 

 over such obstacles. A fleet of thirty ironclads did not affect 

 the rays during the naval manoeuvres, and during the yacht race 

 I was able to transmit my mes.sages with absolute succe.ss across 

 the very high buildings of New \'ork, the upper storeys of 

 which are iron. 



