Royal Society. 227 



glass or sealing-wax, so that the gold leaves diverge. Now raise 

 the upper plate by a glass handle : the leaves collapse in pro- 

 portion as it is raised and again diverge as it is depressed. It 

 should be recollected that the plates are electrified by the same 

 electricity, and are always metallically connected by the fine wire, 

 in which respect this differs from ordinary induction experi- 

 ments. It may be said that here the mechanical force is given 

 by the hand ; but this is only in part, the repellent effect of 

 electricity does part of the work and would be therefore ex- 

 pended ; it is analogically as though a man were to add his 

 force to the piston-rod of a steam-engine, which would not pre- 

 vent the loss of heat by the dilating steam. I had hoped to 

 have carried the experiments further and examined the relative 

 quantities, but unfortunately I have no time for such inquiry, 

 and must leave it to others moi'e happily circumstanced. 



Yours, &c., 



W. R. Grove. 



XXIX. Proceedings of Learned Societies. 



KOYAL SOCIETY. 

 [Continued from p. 163.] 

 June 21, 1855. — The Lord Wrottesley, President, in the Chair. 



r|"lHE following communication was read : — 

 ■'- " Experimental Researches on the Movement of Atmospheric 

 Air in Tubes." By W. D. Chowne, M.D. 



In the year 1847, the author of this paper made numerous expe- 

 riments for the purpose of ascertaining what are the conditions under 

 which atmospheric air is placed with regard to motion or rest, when 

 within a vertical tube having one extremity communicating within 

 the interior of a building, and the other in the open atmosphere. 



The paper now submitted to the Royal Society contains the results 

 of investigations undertaken in the year 1853 and continued to the 

 present time, to ascertain whether the ordinary state of atmospheric 

 air contained in a vertical cylindrical tube, open at both ends, and 

 placed in the still atmosphere of a closed room, is one of rest or of 

 motion ; and if of motion, to investigate the influences of certain 

 changes in the condition of the atmosphere which either produce, 

 promote, retard, or arrest the movement. 



He demonstrates, by a series of experiments, that when a tube, 

 open at both ends, is placed in a vertical position, every precaution 

 being taken to exclude all extraneous causes of movement in the 

 surrounding atmosphere, an upward current of air is almost imme- 

 diately established, and continued so long as these conditions are 

 maintained. 



The experiments were made in a room 12 feet square by 8 feet 

 6 inches high ; the window and chimney being carefully secured, and 



