1863.] 683 



the influence of a lining within the experimental tube on the radiation. 

 A ring of blackened paper, for example, not more than l inch in 

 width, placed within a polished brass tube, radiated, when dry air 

 was permitted to enter the tube, a quantity of heat sufficient to urge 

 the needle of the galvanometer through an arc of 56 ; while, when 

 the ring was removed, the radiation from the whole surface of the 

 tube produced a deflection of only 7*5. 



The author finally examines the diathermancy of the liquids from 

 which the vapours made use of in his experiments were derived ; and 

 the result leaves no shadow of doubt upon the mind, that if any 

 vapour be a strong absorber, the liquid of that vapour is also a strong 

 absorber. The phenomenon is one in which the individual mole- 

 cules are implicated, the molecule carrying its power as a radiant 

 and an absorbent through all its states of aggregation. The order of 

 absorption in liquids and vapours is precisely the same. These facts 

 revive thoughts regarding the connexion between radiation and con- 

 duction, to which the author has already given expression. In a 

 future memoir he hopes to throw additional light on this important 

 subject. 



XXI. "Account of Observations of Atmospheric Electricity 

 taken at Windsor, Nova Scotia." By JOSEPH D. EVERETT, 

 M.A., F.R.S.E., Professor of Mathematics, &c. in King's 

 College, Nova Scotia. Communicated by Professor WIL- 

 LIAM THOMSON. Received June 18, 1863. 



1 . The observations here described were taken at my house, which 

 is on the College hill, Windsor, in latitude 44 53' 34" N., and 

 longitude 64 8' 30" E. They were taken at a landing -window 

 looking N.E., whose sill is 27 feet above the ground. There is a 

 very clear view from the window, and no trees, buildings, or other 

 obstacles to screen it from the full effect of atmospheric electricity. 

 The ground slopes away on the N.E., E., S.E., and S., and is nearly 

 level in other directions, rising slightly, however, for the first 20 

 yards on the N.W. The surrounding country is undulating, with* 

 the exception of a stretch of flat alluvial soil which runs past the 

 base of the College hill, and to which the ground slopes away from 



