6J7 



Chemistry. — "Investü/atmis on the Temperatare-Ccëfjicie^its o/ 

 the Free Moleculai' Surface-Energij of Liquids from — 80^ C. 

 to 1650^ C." XIV. Meatiurewents of a Series of Aroiiuitic 

 nnd Heterocyclic Suhstances. Vty Prof. Dr. F. M. JAiaiKR aiul 

 Dr. Jul. Kahn. 



(Communicated in the meeting of September 25, 1915). 



§ 1. In the present paper the results are piiblislied, obtained with 

 the measurements of the surface-energy of the following 28 compounds ; 

 these measurements may be considered as a supplement of the 

 formerly published researches with aromatic and cyclic derivatives: 



\-%A-ChIorodinitrobenzene; [jaia-Dibromobenzene; lodohemene; ortho- 

 Broiiiotolueiie ; Phenol; A-2-i-üinitrophenol; 2-4:-Q-Trichlorophe7i.ol; 

 jxini-Nilrophenetol; 2- N itro-re.sorcine ; Veratrol; -^^-h-Dinitro-vevatroI; 

 Etlujl- Cmnamylate ; Anisnldehijde ; Benzophenone ; 3-4-3'-4'- Tetra-chloro- 

 heiizoplienone ; 2-A-2' -^' - I'etracldotvhenzophenonebichloride ; Afoiumie- 

 thi/laniline ; Nitrosomethylaniline ; Diisobutylaniline ; Diphe)iylamine ; 

 Dibenzyhimiv.e; Azoxybenzene ; u-JJihydrocniiipao/enic Acid; Ethyl-a- 

 JJihydro-ciniipholenate ; tt-Furfurol; Thioph.eiie; and Piperidiiie. 



The sjiecific gravities were determined in the way previously 

 described, either by means of a dilatometer, or by the aid of the 

 pycnonieter, or finally in some cases by a hydrostatical method. 

 Of some substances only such small quantities were available, that 

 it appeared impossible to determine these specific weights with 

 sulilicient exactitude; or there were other causes, which prohibited 

 these determinations in some cases. It is more especially the very 

 rapid evaporation of many of the higher melting substances, which 

 causes the formation of a crystalline layer round the fine platinum 

 suspension-wire of the immersion-conus, and which of course must 

 appear a serious obstacle for the exact determinations of the 

 density required. 



40'- 



