440 KANSAS CITY REVIEW OF SCIENCE. 



experiments. The results, it will be seen, are highly encouraging : 'Yesterday,, 

 May 17th, I telegraphed successfully across the Tay, opposite to Glencarse,. 

 where it is about half a mile broad. The action on the needle was strong, and 

 the same battery power would cross, I think, at Broughty Ferry.'" 



The dock authorities at Liverpool invited him to exhibit his invention on 

 the Mersey, but owing to his apparatus having been deranged, his experiment in 

 England was not successful. This caused skepticism as to the merits of the dis- 

 covery, and he made renewed tests Avith it on an extended scale on the Tay. These 

 fully realized his expectations. The Dundee Advertiser of July 10, i860, con- 

 tained a letter to the editor, in which Mr. Lindsay wrote : 



" During last week I was engaged in making a telegraphic experiment across 

 the Tay below the Earn, at a place where the river is more than a mile broad. The 

 experiment was successful, and the needle was strongly moved, but, as I had- no 

 person with me capable of sending or reading a message, it was not attempted." 

 Meanwhile he had exhibited his scheme to the savants of the British Asso- 

 ciation at the meeting in Aberdeen in 1859. Experiments were made with it 

 across the river Dee, and he read a paper describing its theory to the Mathemat- 

 ical Section, in the debate on which Lord Rosse, chairman of the section, and 

 other leading scientists took part. Before quoting the condensed report of this 

 paper, it may be well to quote the 'passage in Mr. Preece's paper on "Tele- 

 phones," rea;d at Southampton last week, in which he adverts to an experiment 

 exactly on the lines of Mr. Lindsay's scheme : 



" Mr. Preece had recently tried an extremely interesting experiment between 

 this place (Southampton) and the Isle of Wight — namely, to communicate across 

 seas and channels without the aid of wires at all. Large metal plates were, im- 

 mersed in the sea at opposite ends of the Solent — namely, at Portsmouth and 

 Ryde, six miles apart, and at Hurst Castle and Sconce Point, one mile apart. 

 The Portsmouth and Hurst Castle plates were connected by a wire passing through 

 Southampton, and the Ryde and Sconce Point plates by a wire through Newport; 

 the circuit was completed by the sea, and signals were passed easily so as to read 

 by the Morse system, but speech was not practicable with the telephone." 



The following is the report of the paper on "Telegraphing without Wires," 

 read by Mr. J. B. Lindsay to the Mathematical Section of the British Association, 

 at its meeting in Aberdeen, in September, 1859, which appeared in the Dundee 

 Advertiser. After relating various minor experimerfts, he proceeded to describe 

 his process, saying : 



" Recently he had made additional experiments, and succeeded in crossing 

 the Tay where it was three-quarters of a mile broad. His method had always 

 been to immerse two plates or sheets of metal on the one side, and connect them 

 by a wire passing through a coil to move a needle, and to have on the other side 

 two sheets similarly connected, and nearly opposite the two former. Experiments 

 had shown that only a fractional part of the electricity generated goes across, and 

 that the quantity that thus goes across can be increased in four ways : First — by an 



