128 MEETING OF THE BRITISH ASSOCIATION. 



ber, now going forward, to learn the force of terrestrial magnetism 

 at different places at similar times. — Professor Hamilton explained 

 his views as to the variation in orbits, improving upon the system of 

 La Grange. — Mr. ]\PCullagh offered a beautiful generalization of 

 planetary status. — Mr. Kane offered some observations on the inter- 

 ference of sound. — The section then dissolved. 



Sub-Section A. — Mr. Hodgkinson detailed some experiments in 

 reference to ^the collision of beams and piles, and the elasticity of 

 timber under circumstances of collision. — Mr. Mallet read a paper 

 on the fracture of bars of cast-iron. — Mr. Ettrick submitted to the 

 section a model of an astronomical clock, more perfect in its com- 

 pensation, and independent of the motion of the pendulum. — Mr. 

 Pritchard exhibited an improved microscope. — 3Ir. Grubb made some 

 very able and practical observations on an improved model for 

 mounting an equatorial, adopted by Edward J. Cooper, M. P., of 

 Makeree Castle, county Sligo. Mr. Cooper bore testimony to the 

 excellence of the instrument, as also to the talent and perseverance 

 of Mr. Grubb, in his scientific inprovements and intentions. — Mr. 

 Stevelly produced to the section an improved barometer. — Lieute- 

 nant Denham, R. N., made some interesting observations upon the 

 effects of vibration upon iron railways, and especially where they^ 

 passed over tunnels. — Dr. Lardner delivered some observations upon 

 certain principles connected with railroads. Mr. Vignolles next ad- 

 dressed the section, and detailed several instances coming under his 

 own observation, to shew that in railways where the curve has less 

 than a quarter of a mile, no danger had ever occurred. 



Section C. — Geology and Geography. — Professor Whewell ex- 

 plained his views respecting heat in the production of geological 

 phenomena. — Professors Murchison and Sedgwick gave a descrip- 

 tion of the geological character of the slate country of Wales, com- 

 ing after the coal formation, and a great extent of rocks and fossils, 

 not previously examined, and entered into an explanation of the Si- 

 berian and Cambrian systems. — Professor Jacob entered into an ex- 

 planation of some fossil madrepores, found in the Queen's County. 

 — Several other communications were made, and the section was 

 dissolved. — Professor Griffith, in the evening, at the Rotundo, men- 

 tion that the Wollaston medal had been awarded to Professor Agas- 

 si z. 



Section D. — Zoology and Botany — Several members of the 

 section proceeded to Howth on a botanical excursion. 



Section E. — Anatomy and Medicine. — The proceedings opened 

 by a paper from Dr. O'Beirne, explanatory of his peculiar views on 

 the functions of the bowels, and giving some additional cases in cor- 

 roboration of the accuracy of his published work — Dr. Osborne 

 made a most important communication on the effects of cold on the 

 human body. — Surgeon Hutton gave a report of a peculiar case of 

 disease of the brain, attended with idiocy, and congenital dislocation 

 of the hip joint. — Dr. Handy side, of Edinburgh, stated a case of a 

 similar nature, corroborating the views, and establishing the impor- 



