Royal Society. 461 



glob'ales are formed in the mesenteric glands, with the exception 

 of the colouring matter, which they obtain on exposure to air in 

 passing through the lungs. 



The Bakerian Lecture by Mr. Brande was next commenced 

 reading — " On the composition and analysis of the Inflammable 

 Gaseous compounds resulting from the destructive distillation of 

 coal and oil, with some remarks on their relative heating and il- 

 luminatinc; powers." 



Nov. 18, — The Bakerian Lecture was concluded. In the first 

 part of this lecture Mr. Brande attempts to show that no other 

 compound of carbon and hydrogen can be demonstrated to exisc 

 than that usually called olefiant gas, consisting of one part of 

 carbon and one of hydrogen ; and that what is usually called 

 carburetted hydrogen is in fact a mixture of hydrogen and ole- 

 fiant gases. The truth of his opinion is supported by the author 

 by various experiments on gases obtained from coal, oil, and other 

 substances. He supposes that many of the products obtained by 

 destructive distillation of coals, &;c. are of secondary formation, 

 and result from the mutual action of the gases first formed. A 

 peculiar compound of hydrogen and carbon is thus formed, by 

 passing pure olefiant gas through a tube containing red-hot char- 

 coal, sjmilar in appearance to tar, but possessing the properties 

 of a resin. Sulphuret of carbon was formed by the mutual action 

 of sulphuretted and carburetted hydrogen. Some new modes of 

 analysing gaseous mixtures were also pointed out in the first part. 



The second part related to the illuminating and heating powers 

 of coal gas, and of oil gas. The illuminating powers of olefiant, 

 oil, and coal gases are stated to be to one another nearly as 3, 2, 

 and 1 ; and the ratio of their heating powers to be nearly simi- 

 lar, that from coal being greatest, and that from olefiant gas the 

 least. In this part the advantage in point of illumination by em- 

 ploying many jets in the burners (instead of one) placed so near 

 each other that the different flames can unite, was ilkistrated by 

 experiments. 



The lecture concluded with comparative experiments on ter- 

 restrial and solar light. Gas lights, even when concentrated so 

 as to produce a sensible degree of heat, do not affect the colour 

 of muriate of silver, nor a mixture of chlorine and hydrogen gases; 

 while- the concentrated brilliant light of charcoal submitted to 

 galvanic action not only affects the muriate but causes these gases 

 to unite — sometimes with explosion. Concentrated moonlight 

 did not affect either of these tests. 



A paper '* On the, Elasticity of the Lungs," by Dr. Carson, 

 was commenced reading. 



Nov. 25. — Finished the reading of Dr. Carson's paper. 



ROY.il. 



