96 Chronicles of Science. [Jau., 



author shows that carbonic oxide is not decomposable by foliage, 

 and considers this as confirming his view, that leaves simultaneously 

 decompose carbonic acid and water C0 2 + H 2 = CO,H 2 , 2 , 

 Oj being liberated, C0,H 2 expresses the relation under which 

 carbon is united with the elements of water in cellulose, starch, 

 sugar, &c, i.e. in the important principles elaborated by the 

 leaves, the composition of which is represented by carbon and 

 water. In the third part of his investigations the author shows 

 that detached leaves, kept in shade for many days, with the cut end 

 of the petiole in water to prevent desiccation, preserve the power 

 of decomposing carbonic acid whenever brought into sunshine. 

 It is necessary that they be kept in oxygen, for in darkness oxygen 

 is slowly transformed by the leaf into carbonic acid, through an 

 operation answering to respiration in the animal. A healthy leaf, 

 however, decomposes in sunshine far more carbonic acid than it 

 forms in darkness. In eighteen experiments with, oleander leaves, 

 exposed to the sun from 8 a.m. to 5 p.m., in an atmosphere rich 

 in carbonic acid, a square metre of foliage decomposed, on the 

 average, over a litre of carbonic acid per hour, while in darkness 

 only -rwths of a litre of carbonic acid were produced per hour. 

 In the complete absence of oxygen, leaves, as animals, die from the 

 impossibility of respiration. Boussingault and his assistant, Lewy, 

 were the first to analyse the air contained in a well-manured soil, 

 which they found to be rich in carbonic acid. He has since examined 

 the air contained in a branch of oleander in full vegetation, and found 

 it to contain nitrogen, 88 '01 per cent.; oxygen, 6*64 per cent.; 

 carbonic acid, 5 " 35 per cent. ; being about the same composition 

 as the air of a well-manured soil. He now promises to demonstrate 

 the direct formation of saccharine matter in leaves by the action 

 of sunlight. These researches, obviously, have a most important 

 bearing upon the distinctive functions of plants and animals, 

 since it appears that oxygen is equally necessary to both. 



5. CHEMISTEY. 



(Including the Proceedings of the Chemical Society.) 



Beyond the announcement of the discovery of a new metal by 

 MM. Meinecke and Bossier,* there is no great novelty to record in 

 our present Chronicle. These gentlemen mention that in the 

 course of a mineral analysis they have found a metal, allied to 

 those of the alkaline series, which gives a sharp dark-blue line in 

 the spectroscope in a different position to that given by Indium. 

 They promise a further account of the metal in a short time. 

 * ' Zeitschrift fur Chemie/ H. xix., p. 605. 



