506 
Monpay, May 111, 1857. 
JAMES HENTHORN TODD, D.D., Presipenv, 
in the Chair. 
James AntHoony Lawson, Q.C., was elected a Member of 
the Academy. 
Professor Hennessy read a paper on the Distribution of 
Heat over the island of Great Britain. 
The President read the following note :— 
“‘ Sir William Rowan Hamilton wished to hand in a me- 
morandum of the following ‘General Expression by Quater- 
nions, for Cones of the Third Order,’ which he hoped to be 
allowed to develope and illustrate at some subsequent meet- 
ing of the Academy during the present Session. The equa- 
tion in question is, 
Sqpq'pq'p = 3 (A) 
where p is the variable vector (or side) of the cone of the third 
order, drawn from its vertex as the origin; while gq, q’, g’, are 
three arbitrary but constant quaternions, which may be re- 
garded as fixed parameters of the surface.” 
The following Memorial to Lord Palmerston was read :— 
* To the Right Honourable Lord Palmerston, §c., §c. 
“¢ May IT PLEASE your LorpsuHIP, 
‘We, the President and Members of the Royal Irish 
Academy, beg leave to address you on a subject of great sci- 
entific interest and importance. 
‘* We have learned with much regret that the Lords of 
the Admiralty have decided upon abandoning all further 
