( 3S7 ) 



13. Finally wo iiiny foiubiiie our results with those of Nrwcomh 

 and also with those derived by Fkanz. ^) 



For the correction of the inclination we find: 



Newcomb 'J 868 öi = — 0"15 weight 3 

 Franz 1892 +0.37 1 



Bakh. 1899 —0.19 3 



Mean result ff/r= — 0"09 



The correction of the inclination is thns found to be small. 

 For the correction of the longitude of the node we tind : 

 Newcomb 1868 ö (9 = -\- 4"5 w^eight 3 

 Franz 1892 + 7.4 1 



Bakh. 1899 -f 11.5 3 



Mean result 1885 d 6* = -f- 7"9. 

 As Newcomb found for 1710 (f z=z -1^" {Re.^earckes p. 273), 

 we obtain : 



Correction of the centennial motion = -|- 14". 



Physics. — ''(hi the critical miiiny- point of two liquids'. By 

 J. P. KuENEN. (Commnnicated by Professor van der Waals 

 in the meeting of October 31, 1903). 



A critical mixing-point of t^vo liquids is in general a point where 

 two coexisting liquids become identical in every respect : it corresponds 

 to a plaitpoint or critical point of the two-liquid plait on van der 

 Waals's tf'-surface or of its projection in the ^•olulU(vcomposition 

 diagram, the socalled saturationcurve for the tw^o liquid phases ; the 

 term is used more especially to denote the condition, where the 

 liquids arc at the same time in equilibrium W'ith their saturated 

 vapour. In the v — ,i' diagram this condition corresponds to the point 

 of contact betw^een the tAVO-liquid curve in its critical point with the 

 vapour-liquid curve : in this condition a change of temperature Avill 

 either make the critical point appear outside or disappear inside the 

 vapour-liquid curve. The contact sometimes takes place on the inside 

 of the latter curve and the two-liquid curve then lies entirely in the 

 metastable and unstable parts of the diagram, or it lies outside in 

 the stable part of the figure. In other cases it is the vapoui- curve 

 the ci-itical jtoint of which comes into contact with a two-liquid ciu've, 

 but whatever the case may be, the geometrical conditions are the 



') Tiie coml)ined results of Franz from the observations at Königsberg and at 

 Göttin^en have been considered in my second paper. {Added Dec. I'JOoj. 



26* 



