The London, Edinburgh and Dublin philosophical magazine and journal of science . rease insize while the volume increased to v2 and the external pressureto «r0, and this value would be reached if the bubbles couldbe supposed to increase gradually till the whole mass reachedthe state of vapour. Long before this final condition could bereached, however, the liquid portions of the mass, whichinterlace the bubbles and fill the spaces between them, wouldbe drawn out into thin films, and the conditions would be suchthat the foregoing reasoning could not be applied. Theaction of the distended surface
The London, Edinburgh and Dublin philosophical magazine and journal of science . rease insize while the volume increased to v2 and the external pressureto «r0, and this value would be reached if the bubbles couldbe supposed to increase gradually till the whole mass reachedthe state of vapour. Long before this final condition could bereached, however, the liquid portions of the mass, whichinterlace the bubbles and fill the spaces between them, wouldbe drawn out into thin films, and the conditions would be suchthat the foregoing reasoning could not be applied. Theaction of the distended surface film, in fact, will be such as todraw the liquid parts which fill the spaces between the bubbles Transformation from the Liquid to the Gaseous State. 237 into spherical drops, so that a stage is ultimately reached inwhich the mass consists of a system of spherical drops sur-rounded by their own vapour (fig. 4). The state of affairs is now reversed, for instead of havingvapour in contact with a concave liquid surface, and therefore Fig. 4.—Liquid drops surrounded by o o o°ooo o Xo oo >5°;°°%oo°o<?o ^000oo0oo000°o0ouo0on D o O Oo000 O On O O O 0oOv 0°o00°no o o o^°o o o o£o oo°2°oono 0u0o o o 0 oo ° o0 o Soooo o o p oo uo~oo°o° 0^°oSo°o0 o oo o oo ooo,o o0,o^o °§o oo0o o^o°oOOoo_o o_o Oqo o o o o o o oxo oo, °0 0n000° ° o^ ^o0 0 o^o o £. o o o o -0-o-q 3 0°0 o o at a pressure less than w0, the normal saturated vapour-pressure,we have saturated vapour in contact with convex liquid sur-faces, and therefore at a pressure ot, greater than w0. Hence, in this limit, we may take the pressure on theenclosing piston to be that of the saturated vapour, namely -or,the mass will be subject to an external pressure greater than-bjo, namely p = vr, and this brings us into the region ON(fig, 2) of the isothermal which lies above the normal pressureline BD. In this it is assumed that the mass is largely inthe condition of saturated vapour, and that
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Keywords: ., bookcentury1800, bookdecade1840, bookidlondon, booksubjectscience
