'r^nt^Hgm^^9mmm^mmmm^mmmm 



Fig. 



Fig. o. j^^ 



Fig. 6. !^: 



^IG. 7. 



J 



Note reversed lines on Figures 5, 6, and 7, marked with a cross. 

 Fig. 7 is in the ultra-violet portion of the spectrum. 



