Richardson & Comptcw. 



90 



30 



70 



60 



50 



40- 



50 



?0 



Fm. 3. 















































25 A 































^23\' 















\ 





















v^iA 









{ 









\ 





















Al 













Pt 



0- 











































/ 









/ 









/ 











-E-5 



•1-5 



•! -2 -3 -4 -5 -6 7 



•9 1-0 H 1-2 







Mg 

















-V 



\y 



-e-o -is 



