374 Scientific Intelligence. 



VICK-PRESri)ENTS. 



Joseph Clarke, M. D. ; Colonel E. Hill ; The Provost ; William Brooke, 



M. D. 



OFFICERS. 



Treasurer. — William Brooke, AI. D. 



Secrelaries.-^lke\. J. H. Singer, D.D., F. T. CD.; Rev. Francis Sadleir, 

 D. D., S. F. T. C. D. 

 Secretary of Foreign Correspondence. — Colonel K, Hill. 

 fAbrarian. — Rev. W. H. Drummond, D. D. 



COMMITTEE OF SCIENCE. 



His Grace the Archbishop of Dublin ; Joseph Clarke, M D. ; The Pro- 

 vost ; Rev. F. Sadleir, D. D. &c. ; Sir C. L. Giesecke ; Rev. R. MacDon- 

 nell, D. D., F. T. C. D. ; Rev. Dionysius Lardncr, LL. D. 



COMMITTEE OF POLITE LITERATURE. 



Rev. J. H. Singer, D. D. &c. ; Andrew Carmichael, Esq. ; Samuel Lit- 

 ton, M. D. ; Rev. C. R. Elrington, D. D., F. T. C. D. ; Hev. W. H. Drum- 

 mond, D. D. ; George Kiernan, Esq. ; Rev. John Darley, F. T. C D. 



COMMITTEE OF ANTIQUITIES. 



Colonel E. Hill ; William Brooke, M. D. ; Isaac D'Olier, LL. D. ; Rev. 

 Henry H. Harte, F. T. C. D. ; Thomas H. Orpen, M. D. ; Hugh Fergu- 

 son, M. D. ; Sir William Betham. 



An essay " On a New Species of Apparatus designed for popular illustra- 

 tion of Lectures on Mechanical Subjects, by the Rev. D. Lardner, LL. D." 

 was read. A large sectional model of a steam-engine was at the same time 

 exhibited as a specimen of the proposed apparatus. 



April 2. — Dr Lardner's essay " On a New Species of Apparatus," &c. 

 was unanimously voted for publication in the Transactions. 



An' essay entitled " Theory of Systems of Rays, by William Rowan 

 Hamilton, Esq. T. C. D." was afterwards laid before the Council, and re- 

 ferred for reading to its next sitting. 



Art. XXXVIL—SCIENTIFIC INTELLIGENCE. 



I. NATURAL PHILOSOPHY. 

 ASTRONOMY. 



1. Figure of the Earthy deduced from observations on both hemispheres. — 

 Oh the 2d March 1827, M. Duperrey read an account of his experiraeiits 

 with an invariable pendulum, during his voyage in the Coquille. The 

 principal anomalies have been observed in the Isle of France, Mons, Guam, 

 and Ascension. At the Isle of France M. Duperrey found, as Freycinet 

 did, that the pendulum made 13 or 14 oscillations in a day less than it 



ought to have done, by supposing the flattening of the earth to be — -, as 



the lunar theory makes it. At the Isle of Ascension we found, as Cap- 

 tain Sabine did, an acceleration of from five to six oscillations, even by 



