410 Eggleston — Eruptive Rocks at Cutting sville, Vt. 



stages in the advance of differentiation, possibly inter- 

 rupted, and again renewed, by further assimilation of 

 country rock. 



List of Chemical Analyses. 





I 



II 



III 



IV "1 



T VI 



VII 



SiO, 



57-44 



46-47 



60-88 



57-64 



67-30 



3804 



AL0 3 



21-60 



16-86 



20-75 



23-31 



17-44 



13-50 



Fe,0 3 



•20 



3-21 • 



•63 



1-22 



1-56 



6-21 



FeO 



2-62 



7-72 



113 



•55 



1-76 



15-85 



MgO 



109 



516 



•17 



•22 



014 



7-26 



CaO 



2-90 



9-45 



1-08 



•67 



100 



12-42 



Na-O 



7-36 



4-20 



6-35 



10-48 7-32 7-08 



3-21 



K„6 



4-12 



1-35 



5-57 



509 4-81 4-78 



1-68 



H..O + 



■58 



•45 



•88 



•24 



005 



0-48 



hIo — 



•03 



•04 



•03 



•02 



005 





CO, 



•39 



Trace 



•61 



None 







Ti0 2 



•69 



2-86 



•35 



•15 



0-17 



106 



Zr0 2 



•02 



None 



Trace 



• 12 



0-08 





PA 



•38 



115 



Trace 



Trace 



004 





so 3 



None 



None 



None 



Trace 



None 





CI 



■07 



•06 



•18 



•02 







f 



•05 



■10 



•05 



•06 







Cr,0, 



None 



None 



None 



None 







MnO 



•14 



• 23 



•22 



•10 



016 



1-21 



BaO 



■26 



Trace 



•02 



None 







SrO 



■04 



•04 



Trace 



Trace 







FeS, 



•15 



■21 



•61 



•08 







Fe 7 S 8 



•14 



•08 



•13 



•05 







Li 2 



None 



None 



None 



None 







Sum 



100-27 



99-64 



99-64 



100-02 



101-61 



100-92 



Specific gravity - 











3-518 



I = Hornblende-biotite syenite (laurvikose), H. E. Merwin, analyst. 

 II = Essexite (andose), H. E. Merwin, analyst. 

 Ill = Sodalite-nephelite syenite (nordmarkose), H. E. Merwin, analyst. 

 IV = Tinguaite (miaskose) , H. E. Merwin, analyst. 

 V (partial) = Zircon-rich pulaskite porphyry, H. E. Merwin analyst. 

 VI = Augite syenite (nordmarkite, nordmarkose), C. D. Test, analyst. 

 VII — Barkevikitie hornblende from hornblende-biotite syenite of analysis 

 I, C. D. Test, analyst. 



