PROCEEDINGS 



OF 



THE ROYAL IRISH ACADEMY. 



1843. No. 39. 



February 27. 



SIR Wm. R. HAMILTON, LL.D., President, in the Chair. 



Sir WilHam Betham exhibited to the Academy an ancient 

 shoe, found in a bog on the property of Sir Nicholas Fitz- 

 simon, in the King's County. 



Professor Lloyd read a supplement to a former paper 

 "on the Determination of the Intensity of the Earth's Mag- 

 netic Force, in Absolute Measure." 



In a paper recently communicated to the Academy, the 

 author had shown that the ratio of the coefficients of the first 

 two terms, in the expression for the moment of the force 

 exerted by a deflecting upon a suspended magnet, was gene- 

 rally given by the formula 



h = 2— —3-^1 



M m' 



in which M and M3 denote certain integrals depending on the 

 law of distribution of free magnetism in the deflecting mag- 

 net, and m' and M'3 the corresponding quantities for the sus- 

 pended magnet. It was further shown, that when the mag- 

 nets were small, this formula was reduced to 



VOL. II. 2 G 



