275 
procal surface, I apply to it the general theory, and show how 
it is that the degree of the reciprocal of that reciprocal reduces 
to m. 
‘¢ Finally, I apply the theory to the case of ruled surfaces, 
for which it is easy to see that the degree of the reciprocal is 
always equal to the degree of the surface, and I show how it 
follows from the general theory that this is the case.” 
The paper was referred to the Council for publication. 
Parke Neville, Esq., presented some specimens of peat- 
moss, and part of a rope or cable, formed of heath, found 
about ten feet under the surface of the street, in an excavation 
made lately in St. Michael’s Hill, opposite the western en- 
trance of Christ Church, Dublin. 
