258 Proceedings, (See., for 1886. 



April Sth. 



Present, the President (in the chair) and 27 members and 

 associates. 



Mr. John Dennant was duly elected by ballot a country member 

 of the Society. 



The President (vacating the chair, which was taken by the Hon. 

 Librarian, Dr. Neild) read Mr. Campbell's paper on " The Stability 

 of Structures in regard to Wind Pressure." 



Dr. Iffla would have liked to see a larger collection of recorded 

 maximum pressures. The great discrepancies shown in those 

 produced indicated the need of more extended observations. 



The President said that anemometers were often destroyed by 

 the excessive pressure. 



Mr. M'Lean mentioned a simple method and apparatus for 

 testing wind pressure. 



Mr. Rusden thought the imperfection of the records arose from 

 the limited width of the most violent currents or gusts of wind and 

 the paucity of anemometers. 



Mr. Sutherland agreed, and doubted whether the most violent 

 gusts were ever properly recorded by anemometers. 



The President could not credit the records, which appeared to 

 him impossible. If they were correct, railway carriages would be 

 frequently blown over, and, in fact, would require 50 tons of ballast 

 or a gauge of 20 feet. 



The President read a letter of apology from Mr. Griffiths 

 (who was to have read a paper that evening) for unavoidable absence 

 in Sydney. 



Mr. Selby, in another room, exhibited and explained the action 

 of Crooke's Radiant Matter Tubes. 



May Uth, 1886. 



Present, the President (in the chair) and 16 members and 

 associates. 



The following gentlemen were duly elected by ballot as members 

 of the Society:— The Hon. F. T. Derham, M.P., and Messrs. 

 Arthur Lynch and A. C. Wannon. 



Also as associates: — Messrs. R, W. Chapman, James T. Cole, 

 and Sydney Horsely. 



The President called attention to the handsome present made by 

 Mr. Selby to the Society's Library, of Alexander Von Humboldt's 

 Vues des CordUleres, original edition of 1810, and of Boscovich's 

 Opera Astronomica, in 5 vols. ^ 



A vote of thanks was accorded to Mr. Selby. 



Mr. G. S. Griffiths read his paper on " Evidences of a Glacial 

 Epoch from Kerguelen's Land, being Comments upon the * Challenger' 

 Reports." 



