PROCEEDINGS 



OF THE 



ROYAL SOCIETY OF EDINBURGH. 



1836. ^'o- S- 



Monday, \st February 1836. 

 Sir THOMAS M. BRISBANE, President, in the Chair. 

 The following Donations were presented : 

 No. 52. of the Map of the Ordnance Survey of Great Britain ; pub- 

 lished by the Board of Ordnance — By the Board. 

 Proceedings of the Berwickshire Naturalists' Club. No. 3.— Sy 

 the Clvb. 



The following Communications were read : 

 1. On the Mathematical Form of the Gothic Pendant. By 



Professor Forbes. 

 The author commenced, by stating the general proofs of the 

 knowledge of the principles of equilibrium displayed by Gothic ar- 

 chitects in the structures (especially) of the pointed style. The 

 adaptation of their edifices was to the combined ends of elegance 

 and strength. The extension of this principle to the case of the 

 Gothic pendant is the chief object of this paper. Sufficiency in 

 point of strength, without redundancy of material, is considered by 

 the author as the primary source of architectural beauty; which he 

 has demonstrated to be the case when the depending Gothic drop 

 is generated by the revolution of the logarithmic curve round its 

 axis. The condition of maintenance of a depending body is, that 

 the increment of the section may be in a constant ratio to the m- 



