260 Proceedings, &G.,for 1886. 



Pasco, E..ISr., Dr. Bride, Dr. Wild, and himself, as members of 

 tlie proposed Joint Antarctic Committee; and he also reported that 

 the Council of the Royal Society had appointed as members of the 

 same committee, himself, Mr. Ellery, Mr. Griffiths, and the two 

 secretaries, Mr. Rusden and Mr. Selby. The new committee had 

 already held one meeting. 



Mr. RusDEN then read Mr. Wakelin's paper '' On the Possibility 

 of the Force Producing Gravitation not Acting Directly on every 

 Particle of a Planet." 



The President said the subject was intricate and difficult, and, 

 though frequently attacked, remained so far unsolved. The paper 

 seemed hard to comprehend, but he invited members to discuss it. 



Mr. Ellery said Mr. Wakelin had before suggested experiments 

 with a special spring to find whether bodies weighed more or less 

 on the side of the earth nearest to or farthest from the sun, but he 

 failed to see the utility of them. 



After some remarks from Mr. White and Mr. Steene, Mr. Ellery 

 suggested that the paper be printed, so that members might all read 

 it before discussing it. This was seconded by Mr. White and 

 carried. 



The Secretary then read Mr. F. A. Campbell's paper on " The 

 Stability of Structures in regard to Wind Pressure (No. 2) — Bridges." 

 Mr. Ellery said that he had constructed an anemometer for record- 

 ing momentary gusts of wind, the results of which were scarcely 

 credible. Wind is not a moving mass, but moves in eddies and 

 gusts, which are extremely local, and usually escape record. 



Mr. Griffiths thought the general velocity of a wind furnished 

 no indication of its occasional local violence. He compared with it 

 a stream of water, the velocity of which is known to vary in every 

 part of a section of its channel. He suggested the indefinite multi- 

 plication of wind gauges. 



Mr. RusDEN, Mr. White, Mr. Steane, and Mr. Ellery corro- 

 borated the views expressed. 



The President quoted from a report from Mr. Waddell, an 

 American engineer in Japan, who stated that American engineers 

 commonly made sufficient provision for wind pressure. Since the 

 Tay disaster excessive allowance had been made for it in England. 

 The American practice has been endorsed by Mr. Baker, President 

 of the mechanical section of the British Association. Americans 

 reckon that a pressure of 30 lbs. to the square foot being sufficient 

 to overturn a railway carriage, it is useless to make the bridge resist 

 more. American bridges stand well on this principle, and it looks 

 like waste to allow for 60 lbs., as is done here and in South Australia. 



July 8th. 

 Present, the President (in the chair) and 17 members and asso- 

 ciates. 



