vih, a. 6 Pratt: Phthalides and Related Compounds 



Oscillation frequency. 



34 3 6 3 8 4000 42 4 4 



407 



3.8 



3.6 



3.4 



1 3.2 



3.0 



» 23 



S 2.6 



I 2,4 



2.2 



2.0 



1.8 



1.6 



1.4 



32 



2. 





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Fie. 6. Curve 1. Pbthalimidene in alcohol. Curve t. Phthalimidene in 

 sulphuric acid. 



