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SCIENCE PROGRESS 



accepting the values for L, T c and p c given in Table I., it 



follows that 



/3 = 0*003223 



The molecular weights calculated from equations (16), (19) and 

 (20) are as follows (for values of L, T c and p c refer to Table I.) : 



Table VIII 



In the case oi the difficultly liquefiable gases, Guye uses a 

 simpler method of calculation. The molecular weights given by 

 equation (15) are found to be too low by amounts proportional 

 to the critical temperatures (absolute) of the gases ; hence 

 instead of (15) Guye writes 



M 



L" (1 + a)(i -b) = R + mT c (21) 



where m is a constant for the gases and a and b are deduced by 

 means of equation (16). To determine the actual value of m f 

 the numerical values of M, L, a, b and T c for oxygen are 

 substituted in the equation (R equals 22*412 as before), the 

 result being that 



m = 0*0000623. 



The following table contains the results obtained by the 

 application of equations (16) and (21) to the data for the 

 difficultly liquefiable gases (values of L, T c and p c are given 

 in Table I.) : 



