Proceedings of the British Association. 325 



tities of orceine. From this circumstance a mimber of phenom- 

 ena in the color of lichens can be explained, which Dr. K. has 

 described in his work on that subject. Prof. L. also states that 

 he has performed many experiments on the legumin of beans, 

 and some other leguminous plants. He has arrived at the con- 

 clusion, that this body is identical with the casein in milk of ani- 

 mals. It has precisely the same composition, and contains the 

 same salts, — (phosphate of potash, potash, magnesia, lime and 

 iron,) — as the casein of milk. Prof L. also mentions, that Drs. 

 Will and Varrentrapp have devised an excellent method for deter- 

 mining the amount of nitrogen in organic bodies. The substance 

 is mixed with a quantity of caustic potash and hydrate of soda, 

 and heated to redness in an ordinary combustion tube. All the 

 nitrogen in the substance escapes as pure ammonia, which is con- 

 densed in a small and neat apparatus, containing dilute hydro- 

 chloric acid. This solution is mixed with chloride of platinum, 

 evaporated to dryness in a water-bath, and the excess of chloride 

 of platinum is washed from the ammonia chloride by a mixture 

 of ether and alcohol. From the metallic platinum which remains 

 after the ammonia chloride is heated to redness, the quantity of 

 nitrogen is to be calculated. In conclusion, the Professor states 

 that he has repeated all the experiments of Dr. B^jpwn on the 

 production of silicon from paracyanogen^ but is not able to con- 

 firm one of his results. His experiments prove that paracyanogen 

 is decomposed by a strong heat, into nitrogen gas, and a residue 

 of charcoal which is exceedingly difficult of combustion. — Dr. 

 Parnell stated that he too had repeated the experiments of Dr. 

 Brown, without being enabled to verify any one of his results. 

 The following papers were also read before the Section. 



On some instances of restrained chemical action ; by E. A, Parnell. 



On some subjects connected with the sulpho-cyanides; by the same. 



On the direct formation of cyanogen, from its elements ; by G. Fownes. 



Experiments showing the possibility of fire from the use of hot water in warming 

 buildings, and of explosions in steam-engine boilers ; by Goldsworthy Gurney. 



On the production of sulphuretted hydrogen by the action of vegetable matter 

 on solutions containing sulphates ; by E. Lankester, M. D. 



On the composition of crystallized diabetic sugar; by R. D. Thomson, M. D. 



On spontaneous combustion; by Messrs. Booth, Hunt, and Hearder. 



Section C. Geology and Physical Geography. 

 Mr. J. E. Bowman read an extensive paper on the Upper Silu- 

 rian Rocks of Denbighshire, and stated that a re-examination 



