dlEMISTRY. 



DCS 



No attempts appear to have been ninde to synthesize the aiialogons 



4-carbon ring* : 



=C-C--. 



I I 



=c— c= 



though aceiiaphtliene, a body in the aroioatic series, without doubt 

 contains such a ring. Fhiorene is a hydrocarbon containing a Scarbon 

 ring, and several known bodies of the fatty series are closelj" allied to 

 the hypothetical 4 and 5 carbon rings. These are furturan, pyrrholiue, 

 succinimide, and parabauic acid. The author adopts the i'oihnving 

 scheme of nomenclature for the 3, 4, 5, and 6 carbon rings: 



He also proposes to distinguish the i)ossible isomers by numbering 

 the carbon-atoms in the ring as suggested by Baeyer {Ber. d. cJiem. Oes., 

 XVII, 900). The author describes fuU.y the methods of preparation and 

 the i>roi)erties of a number of trimethylene derivatives, and promises 

 at an early date to do the same for some tetramethylene derivatives. 



The following table contains a list of the trimethylene bodies witli 

 their chief characters : 



