273 
NovemBER 307TH, 1855. (Stated Meeting.) 
GEORGE PETRIE, LL.D., Vice-PresipEnt, 
in the Chair. 
Tue Secretary of the Council read the following recommen- 
dation of the Council, and moved—“ That the Academy do 
repeal the By-Law, Chapter vit., Section 6, viz. :— 
«¢ «In case of the sickness or absence of any Member of a 
Committee, to be signified to the Secretary of Council, that 
Member of such Committee shall nominate a Member, pro 
tempore, out of the names which have been proposed by the 
Council to fill the Committees, and which have not been 
elected; the Member’s nomination shall then be signified to 
him by the Secretary of Council; and in case the President 
shall approve such nomination, such Member pro tempore shall 
be vested with all the powers of a Member of Council.’” 
Moved by Rey. G. S. Smith, D.D., seconded fs J. M. 
Neligan, M.D., and— 
Resotvep—That the consideration of this Sate be 
adjourned to the Stated Meeting of the 16th March next. 
'_. The Secretary of the Council read a paper, by the Rev. 
George Salmon, on Reciprocal Surfaces. 
«‘ The object of this paper will be better understood by first 
stating the corresponding problems for plane curves, and the 
solution which has been given for them. 
“Ifthe degree (m) of a curve be estimated by the number 
of points in which it meets an arbitrary line, and the class (n) 
of a curve by the number of tangents which can be drawn 
to it from an arbitrary point, then it is known that the 
degree of the curve is equal to the class of the reciprocal 
curve, and vice versa, and that the latter is in general derived 
VOL, VI. 2D 
