348 
Proceedings of tlie Koyal Society of Edinburgh. [Sess. 
XXIII. — Notes on a Correspondence between the French Academy 
of Sciences and the Royal Society of Edinburgh regarding 
the Invention of the Pilot Cable (Cable Guide). By The 
General Secretary. 
(Read June 19, 1922.) 
During 1921 the Academ^r of Sciences of France awarded a medal and 
prize to M. W. A. Loth for various important devices having special 
application to navigation. Among these was mentioned the system of 
the Cable Guide, which is essentially the system of Pilot Cable invented 
by Mr C. A. Stevenson, C.E., and described by him in 1893 in the 
Proceedings of the Royal Society of Edinburgh. In a communication to 
the Academie des Sciences the Council of the Royal Society of Edinburgh 
called attention to this fact and to the further fact that apparently no 
recognition had been given of the pioneer work of Mr Stevenson. 
In a letter of date January 31, 1922, M. Emile Picard, Secretaire 
Perpetuel de I’Academie des Sciences, explained that in awarding the 
prize to M. Loth the Academy of Sciences were guided entirely by the 
efficacy of M. Loth’s ingenious devices, that the report submitted to the 
Academ}^ by V^ice- Admiral Fournier (see Comptes Rendus, December 12, 
1921, Tome 173, p. 1230) did not touch upon the question of priority of 
invention, and that the question of principle did not arise. 
The Council of the Royal Society of Edinburgh after a careful examina- 
tion of Vice-Admiral Fournier’s report considered that this report did 
implicitly credit M. Loth with the invention of the Pilot Cable : moreover, 
in popular accounts of his methods this was explicitly stated. 
The Council, feeling it to be a matter of simple justice to emphasise 
the claim made for Mr C. A. Stevenson as the original inventor of the 
system which had been so effectively developed by M. Loth in recent 
years, authorised the General Secretary to send the following statement 
to the Academy of Sciences, in which the phraseology of the Stevenson 
Patent of 1893 is compared with one of the Sections in Vice-Admiral 
Fournier’s Report:^ — 
“ Priority Note on the Pilot Cable (Cable Guide). 
“The Council of the Royal Society of Edinburgh desire respectfully to draw 
attention to a point which has arisen in connection with a Prize recently awarded 
by the Academy of Sciences. 
