Brief Historical Sketch of the Telegraph, 291 
modern invention for the same purpose previous to the 
Marquis of Worcester’s, contained in his 66 Century of 
Inventions ,” which was published in 1663. In this work 
he affirms that he had discovered u a method by which, 
at a window, as far as the eye can discover black from 
white, a man may hold discourse with his correspondent, 
without noise made or notice taken ; being according to 
occasion given, or means afforded, ex re nata , and no 
need of provision beforehand ; though much better if 
foreseen, and course taken by mutual consent of parties.” 
This means of correspondence he also asserts to have 
been rendered so perfect that it could be put in practice 
6i by night as well as by day, though as dark as pitch is 
black.” On the 21st of May 1684, Dr. Hooke, so much 
celebrated for his mechanical genius, delivered a dis- 
course* to the Royal Society on the method of communi- 
cating one’s mind at a great distance. In this discourse 
he asserted the possibility of conveying intelligence from 
one place to another at the distance of 30, 40, 100, 120, 
&c. miles, “ in as short a time almost as a man can write 
what he would have sent and laid down directions for 
accomplishing it. The whole of this ingenious paper was 
published in Derham’s Collection of Dr. Hooke’s “ Ex- 
periments and observations ,” and from which it appears 
that his contrivance was little inferior to several that have 
been lately proposed for the same purpose. William 
Amontons, an ingenious French philosopher, about the 
year 1702, likewise invented a method of conveying in- 
formation from one place to another by signals ; and it is 
probable without any knowledge of what had been pre- 
viously advanced on the same subject by the Marquis 
of Worcester and Dr. Hooke, as his method seems to be 
much inferior to that pointed out by this last gentleman. 
None of these inventions, however, were applied to 
purposes of utility before the French revolution, when 
