Se Ser ee) Sa ee 
SO ee en ae ee ee eae oe 
W. A. Norton—Force of Effective Molecular Action. 857 
convex to this axis. These two sets of curves have for their 
line of demarcation a curve in which a considerable portion is 
parallel to the axis. This curve answers — k=4°7. The first 
w 
less the tenrperature is much reduced below ordinary tem- 
peratures, For these the smaller values of & obtain. Thecon- 
du mpe 
of m, which is theoretically ee nal to the absolute 
temperature, and so increases the value of & and causes the 
molecular curve to rise. When itis thus brought pe ve the 
critical curve, for which k=4°7, it becomes rtain 
distance beyond 8r concave upw wards, the effective satiny 
begins to decrease ata certain distance beyond 37, and a sudden 
condensation to the molecular distance 37 must 
ensue, as the compression goes on, before the 
istance 8r is reached. en the temperature 
answers to the critical curve the molecular re- 
pulsion is sensibly the same over a considerable 
range of distance, viz. from 8r to 75r. Under 
the same rote: Pires the gaseous mole- 
cules may then separated by any distance 
lying —— rite two extremes. Under ex- 
