346 
the proposal was Dr. Hart’s, or he would not three times have said so. 
It clearly, then, could not have formed part of the paper actually read 
here on June 25, 1855,* as Dr. Hart only communicated the details to 
Mr. Mallet in July; and it is equally clear that Mr. Mallet’s first sugges- 
tion to Government must have differed from that ultimately acted on. 
With respect to M. Thiéry’s plans, I will only quote some words I 
find at page 152 of Mr. Mallet’s work on Artillery,—words written when 
Mr. Mallet was probably more cool than he is this evening :— 
‘‘ Solid reinforce rings have been repeatedly proposed and frequently 
applied to various projects and forms of cannon, but the author believes 
that the peculiar advantages of their application in thin concentric 
lamina, the internal ones of which shall be compressed by an wtial ex- 
tension of the external ones, have never before been distinctly pointed out, 
and their adoption proposed and urged; the essential and radical distine- 
tion being this, that by no arrangement or variation of design can a gun 
be formed of a single ply of rings, whose strength to sustain an internal 
pressure shall be greater than the cohesive power of the material per 
square inch of section; whereas by the subdivision of the rings into a 
number of superimposed plies, each compressing those within tit, the 
strength of the gun may be increased so as to bear an internal pressure 
any required number of times greater than the ultimate cohesive powers 
of the material, in fact, may be increased ad infinitum.” 
I cannot believe, Sir, that this ‘‘ essential and radical distinction”’ has 
disappeared since 1855. Indeed, M. Thiéry tried to make guns in the 
way he thought best, and failed utterly. 
T will not follow Mr. Mallet on irrelevant questions. I regret much 
that I am obliged to take up your time at all in discussmg what can be 
of so little interest. 
The following donations of antiquities were presented to the Aca- 
demy :— 
By the Rey. W. Reeves, for the Rev. John Hamilton, a curious can- 
dlestick, found in a crannoge near Manorhamilton. 
By the President, for Mr. Parke, of Dunally, a large cinerary urn, 
highly ornamented, found, with two others, near Ballymote, county of 
Sligo, in the year 1827. 
MONDAY, JUNE 25, 1860. 
James HentHorn Topp, D.D., President, in the Chair. 
The Presrpent announced that the Academy was called upon that 
evening to elect a member of the Council, in consequence of the resig- 
nation of Mr. Haliday on the Committee of Antiquities. Ordinarily he 
* This view is corroborated by what Mr. Jellett says, viz., that Mr. Mallet’s original 
paper was not more than one-fifth part of the size of his published one. 
a ie te 
