194 



Theory of a Non-Conservative Gas [CH. vm 



C 

 It appears from the form of the differential equation that -y- vanishes 



when 



/WK(H-fK) + 2eH=0 (466), 



is infinite when 



H = |K (467), 



or K = ; and is negative, being equal to 1, when H = 0. If, then, we draw 

 a two-dimensional space (H, K), the quadrant in which H and K are both posi- 

 tive will be divided into three sections by the axes and the two curves of 

 which the equations are (466) and (467). Starting from the axis of K, the 



<^K 



signs of -7- in these three sections are respectively negative, positive and 

 a H 



negative. The curves are therefore roughly as represented in fig. 14. It 



K 



FIG. 14. 



will be seen that they tend to converge for small values of H and K into 

 a single stream line for which at the origin, 



Lt - = 0, and Lt = 0. 



