Royal Society. 63 



hours under a glass bell with a cup of dilute sulphuric acid, passes 

 completely from the alkaline to the acid liquid." 



Page 417. " TERioniDE of Phosphorus, PI 3 = 285. — This is ob- 

 tained when into a thin test-tube, or small flask, containing phos- 

 phorus, and from which the air has been displaced by dry carbonic 

 acid, twelve times its weight of iodine is introduced." 



Page 297. "Such a result indeed is always obtained when the 

 nitric acid is concentrated, and that the bottle or flask (it should be 

 a strong one) is immediately closed by the pressure of the thumb 

 after the acid has been introduced." 



In conclusion, we can conscientiously say, after a careful examina- 

 tion of the book before us, that we have been unable to discover any 

 one respect in which it is superior to the average of elementary works 

 on chemistry, while, as we have pointed out, it frequently falls below 

 the average. If such a work was to be published at all, it is to be 

 regretted that it was issued as one of a series of educational works 

 which have already acquired a certain reputation for general excel- 

 lence, and are " recommended by the Committee of Council on 

 Education." 



VIII. Proceedings of Learned Societies. 



ROYAL SOCIETY. 



[Continued from vol. xxvii. p. 542.] 



February 25, 1864. — Major-General Sabine, President, in the Chair. 



fTPHE following communication was read : — 

 JL " On the supposed Identity of Biliverdin with Chlorophyll, 

 with remarks on the Constitution of Chlorophyll." By G. G. Stokes, 

 M.A., Sec.R.S. 



I have lately been enabled to examine a specimen, prepared by 

 Professor Harley, of the green substance obtained from the bile, 

 which has been named biliverdin, and which was supposed by Ber- 

 zelius to be identical with chlorophyll. The latter substance yields 

 with alcohol, ether, chloroform, &c, solutions which are characterized 

 by a peculiar and highly distinctive system of bands of absorption, and 

 by a strong fluorescence of a blood-red colour. In solutions of bili- 

 verdin these characters are wholly wanting. There is, indeed, a 

 vague minimum of transparency in the red ; but it is totally unlike 

 the intensely sharp absorption- band of chlorophyll, nor are the other 

 bands of chlorophyll seen in biliverdin. In fact, no one who is in 

 the habit of using a prism could suppose for a moment that the two 

 were identical ; for an observation which can be made in a few seconds, 

 which requires no apparatus beyond a small prism, to be used with the 

 naked eye, and which as a matter of course would be made by any 

 chemist working at the subject, had the use of the prism made its 

 way into the chemical world, is sufficient to show that chlorophyll 

 and biliverdin are quite distinct. 



I may take this opportunity of mentioning that I have been for a 



