( 180 ) 



Fia- S. 



liquids- mid solids ^). ViLTiARD e. g. found, tlial wlieii he compressed 

 oxygen at the nsual teniperatnre (iT"") to db 200 atmospheres in a 

 tnbe Avith bromine, this evapoi-ated in a mnch higher degree than 

 corresjionded with the vaponr-tension at the temperatni-e of observation. 

 This ('oukl be observed because, while the oxygen was being com- 

 pressed, the colonr of tlie vaponr grew darker and darker and becanse 

 bromine on decrease of i)ressure was deposited against the ^vall in 

 the form of little drops. 



Prof. Bakhuis Roozeboom -) has already given 

 an explanation of this |)lienomenon by means of 

 the y>--/-loo}), which ap|)lies to the said system of 

 o.rjuicii — hro)ui})(' at 17'', because this temperature 

 lies far above the critical temperature of o.i\i/(/('i/ 

 ( — 111'^) and also abo\e the melting |)oinl of 

 hroiDillC ( — 7,3"). 



Accoi'ding to Hart.mann ") liiis y>-,/-looj) lias the 

 "orm, given in tig. 8. It follows from the great 

 A ^' :x: a y\^q ,^j)(| running l)ack of the vapour-line EllP, 



that the partial pi-ossure of the \apoiii' of 7i I)ctween 11 and /'^must 

 be much greater than the [)rcssure in K. Though increase of [)ressure 

 alone is sufficient to increase the va|»our-lension, the intluence of 

 compressed gases is much greater in consequence of the solution of 

 the gas in the li(iuid. 



It is clear that by increase of the oxygen-tension /o/r// evaporation 

 can be i-eached here, the region licpiid -J- ^'^^P^^'"' having for a cei-lain 

 concentration of A given })lacc to the gas-i-egiou. 



With the systems' CH—a,H,Cl, CH,— CS„ CH— C,H,OII \'iiJ.VRi) 

 found the same phenomenon in an even more striking way. Also 

 with solids YiLT.ARD could ol)serve an increase of the paitial ])ressure. 

 The partial |)ressure of iodine \vas perceptibly increased by an 

 oxygen-pressui-e of ± 100 atmospheres, whereas witli hydrogen a 

 perceptible increase did not occur until at 200 a 300 atmospheres 

 At =t 300 atmospheres methane dissolves very percej^tible quantities 

 of camphor and parafline, even so much that on decrease of pressure 

 the dissolved substances crystallize in visible quantities against the 

 walls of the tube. 



At 300 atmospheres aethylene dissolves rather much J, Avhich on 



1) Hannay and Hogarth. Proc. Roy. Soc. 30, 178, (1880). 

 ViLLARD. Joiirn. de Phys (3) 5, 453 (189G). 



Wood. Pliyl. Mag. 41, 423, (189G). 



2) Die Heterogene Gleichgewichte 2, 99. 



3) Journ, phys. Ghem. 5 425 (1901). 



