40 Proceedings of the Royal Irish Academy. 



He later finds grounds for supposing that -the sulphui- atom in such 

 compounds is tetravalent, existing as a ring member of the type 



C SH C 



the formula for the methylquinoline derivative being 



• /N C— SH— C— C(CH2; : CH— /\ 



I ' CH : CCCHs)— C— SH— C I ' 



N 



We wish to take this opportunity of expressing oiu' thanks to 

 Dr. P. J. Bi-annigan and Dr. E. W. McClelland for help received duiing 

 the work. 



1 J. pr. Chem., 1902, [2], 66, 209. 



