1880.] Presents. 463 



depicted are copied from photographs of carbon under the conditions 

 indicated, and theory has merely enabled me to arrange them in order. 



Fig. 3. 



The photographed spectra of some carbon compounds. 



This map I submit, therefore, bears out the hypothesis of differences 

 of temperature indicated above, for it is seen that, while the blue line 

 gradually thins out, the ultra-violet flutings appear first and grow in 

 intensity. As these increase, the blue flutings become visible, and 

 further as the latter augments and the line disappears, the ultra- 

 violet flutings gradually die out altogether. 



It is philosophical to infer from these observations not only that the 

 line and flutings in question are produced by carbon, but that the blue 

 line (4266), since it is visible at the highest temperature, corresponds 

 to the most simple molecular grouping we have reached in the experi- 

 ments, and the flutings to others more complex. 



Presents, May 13, 1880. 



Transactions. 



Barnsley : — Midland Institute of Mining Engineers. Transactions. 

 Vol. VII. Part 49. 8vo. Barnsley 1880. The Institute. 



Graz : — Naturwissenschaftlicher Verein fur Steiermark. Mittheil- 

 ungen. Jahrg 1879. 8vo. Graz 1880. Das Chemische Institut 

 der K.-K. Universitat Graz von Leopold von Pebal. 4to. Wien 

 1880. The Association. 



Jena : — Medicinisch-Naturwissenschaftliche Gresellschaft. Denk- 

 schriften. Band II. Heft 4. 4to. Jena 1880. The Society. 



