WHY DO CLOUDS FLOAT IN THE AIR?

Wairarapa Daily Times, Volume VII, Issue 1968, 18 April 1885, Page 2

WHY DO CLOUDS FLOAT IN THE AIR?

Meteoroligists are not agreed as to the reason for the floating of clouds. Genuine steam—that is, water in a gaseous stateis, of course, lighter than l -the genuine stoairi is invisible; and » U consist, not of ateam, but of what On erroneously -called steaiiV;'' namely),. ihe mass of partiolos of watcMormed when steam condenses iu the anil The difficulty always has been to explaiiiMiOviJ&ops of water can float in air, :tliah;>lßi they are so much heavier. .The;'old-fashioned explanation was that the ; \ drops were hollow sphoroa, with ainmprisoncd inside. The water absorbed nig're ..Jieat from the sun than the surrounding;-air, and this heat expanded the imprisoned air, thus making a small baloon-or- bubble of the drop. But there nevor was tho slightest proof forthcoming; for this theory, and there were many objections against, it; for instance, the optical" examination of many forms of cloud has convinced physicists that they mustbb composed of minute crystals .of ice,' to which the bubble theory will certainly not apply. The more recent theories havo been worked up into one.which will probably prove to be the true' bile. ',.'. The fact that solids and liqmds tend to condense on their surface thin films of any gas by whiclithey are surrounded isivell known, and the immense difficnJtjLpf getting rid of these films is only too well known. tP many experimenters ;in. some, cases it scemsiiiipossiblo- to detach theskin of condensed gas that attaojjeß'lWlf toth,a inside of a flajik.. The floating jpf motej jn: the airis supposed to depend[on this action. Tho matterof all motes isfar kiyierthan the air in whioh they float, bWeach is supposed to condonse the littlo aShosphere qf gas. around it, If radiated heat-is passing through the air in: which motes are suspended they will absorb far more heat than the surrounding air,' and sqwill warm up their own little'atmosplierea,causing'them to each mote with its attached atmosphere is enabled to float. Exactly.in.the same way each drop of water in the cloud may be considered to float as a mote of water; or rather, it is probably a* mote with a coating of water round it, andi'rbund that again a special atmosphere of its own, bo that each minute drop of. water, in a cloud ia constituted like the earth, only that the solid ground is sunk beneath a relatively vast ocean.