178 On a new graphical Method 
“ To Dr. Hutton, Bedford Row, London. 
“ Caen, Aug. 13, 18. 
** My pEAR Docror,—I have just received a French Mé- 
moire, sent to me by the author, which you will have great plea- 
sure in reading. 
‘¢ | dare say General Rowley will soon have a copy of it, and 
will lend it to you. 
** It is entitled § Mémoire sur l’Effet des Feus verticaux pro- 
posés par M. Carnot: par M. Angoyat,’ of the French Engineers, 
Professor of Fortification in the chief Military College of France. 
The author, in a close investigation of Mr. Carnot’s system of 
defence, with reference mainly to my werk, and to your Tracts, 
has admitted all my reasoning, and adopted all my conclusions. 
At the end of the Mémoire are two articles, which make such 
honourable reference to your works, as cannot fail to give you 
much gratification in perusing. 
“ The attention of the French engineers to the controversy re- 
specting Carnot’s system of defence, has been excited by two 
causes; viz. to determine how far his ideas should be acted upon 
in their own fortifications, and to teach them how to estimate the 
powers of resistance of those works which the Prussians are con- 
structing at Coblentz and Cologne, on this most defective plan. 
The former is set at rest; for the Mémoire may be considered as 
passing sentence upon Mr. Carnot’s System, and that by a body 
of men certainly not prejudiced against him, nor in favour of a 
British military author. And with respect to the other bearing 
of the question, the French engineers are satisfied that the Prus- 
sians are acting upon an insecure and condemned system. 
“ This Mémoire gives some strength to my cause, and I will 
endeavour to push it further to deter the Prussians from proceed- 
ing with this defective scheme. 
“¢ T hope this will find you in perfect health. I shall be in 
England in about two months. 
“¢ Believe me, dear Doctor, 
‘* Yours very sincerely and truly, 
* HowarD Dovuctas.” 
XL. Ona new graphical Method of reducing the Lunar 
stances. By Mr. Henry MEIKLE, 
To Dr. Tilloch. 
Sir, — Ox attentively considering the different methods hi- 
therto used for reducing the lunar distances by mechanical or 
graphical 
