PROCEEDINGS 



OF 



THE ROYAL IRISH ACADEMY. 



1837. No. 5. 



May 8. 



Rev. F. SADLEIR, D. D., F. T. C. D., Vice-President, 

 in the Chair. 



Rev. Thomas M'Neece, F. T. C. D., was elected member of 

 the Academy. 



Mr. Petrie read the continuation of his paper "On the 

 Antiquities of Tara Hill." 



Professor Lloyd read the following extract of a letter from 

 Mr. Bache, President of Girard College, Philadelphia, re- 

 lating to a comparison of the Magnetic Intensity in Philadel- 

 phia, Dublin, and Edinburgh : 



" I availed myself of an opportunity afforded by Professor 

 Forbes, to observe the horizontal magnetic intensity at Edin- 

 burgh, in a locality as far from the disturbing action of the 

 trap rocks, on the north of the town, as was convenient. The 

 place (Canaan Park) adjoins that in which Mr. Dunlop's ob- 

 servations were made. After correcting for rate of chrono- 

 meter and temperature of needle, &c. I get for Edinburgh 

 (Dublin being unity) 0.9592. The dip, as determined by ob- 

 servation of Professor Forbes, (and given in a recent paper on 

 the diminution of magnetic intensity at different heights,) is 

 71° 47'. I applied a small correction for the diminished 



