S40 Mr Connell on the Action of Iodic Acid, S^c. 



course, its analogies with bromine and chlorine greatly prepon- 

 derate *. On the other hand, the non-action of nitric acid on 

 bromine marks a more feeble affinity for oxygen, and is not in- 

 consistent with our preconceived ideas of a body more nearly 

 allied to chlorine than iodine is. The distinctions between the 

 subordinate classes into which simple bodies have been divided, 

 are evidently vanishing before the progress of discovery, and we 

 seem fast approaching to the establishment of an unbroken chain 

 oi' elementary bodies, differing from one another by gradations 

 of qualities which are continually approximating to each other. 

 The discovery of selenium nearly destroyed the class of metals 

 as an exclusive division. That of lithia, and its metallic base, 

 .went far to annihilate the distinctions between alkalis and alka- 

 line earths and their respective bases ; and it is extremely pro- 

 bable that between iodine and sulphur one or more bodies will 

 one day be found to exist, combining many of the qualities of 

 both these substances, and serving to unite them more closely. 

 In the mean time, the more humble task of pointing out new 

 facts in the history of already known substances, tending more 

 closely to ally them, will not be devoid of interest, as contribut- 

 ing in a less degree to the same general result. 



Critical Observations on the Ideas of M. Alexander Brong-niart, 

 relating to the Classification and probable Origin of Ter- 

 ' tiary Deposits. By A. Boue', M. D. Concluded from 

 page 172. 



JVi. Brongniart, wishing to assist the geologist in the discri- 

 mination of deposits by means of the zoological characters, de- 

 tails the peculiarities by which we may distinguish the proteique 

 or upper tertiary soil from the tritonien or the under. We 

 must, however, confess, that the zoological distinctions in this 

 case are not more satisfactory than the mineralogical differences, 



• It is singular that, according to the recent experiments of M. Gual- 

 tier de Claubry (Annales de Chim. et de Phys. xlvi. 221.), the nitrous acid, 

 or hjponitric acid as it is sometimes called, is capable of depriving iodic acid 

 of oxygen, and of being converted into nitric acid under the influence of the 

 presence of water, and at ordinary temperatures •, and thus the relative forces 

 of affinity for oxygen possessed by iodine and nitrogen or its oxides, would 

 seem to be influenced by the temperature. 



