OP EECENT PLANTS IN BEOWN IEON-OEE. 



5 



erosion of the valley is older than the occupation of the district by 

 the Romans. Not only are numerous remains of buildings and other 

 works belonging to the Roman period found in the valleys, but the 

 Roman grave-stones, of which scores are still scattered over some 

 parts of the district, are invariably made of this iron-ore. 



Discussion. 



Mr. Caeeuthees pointed out that the deposit, though of such 

 thickness and importance, was essentially a bog iron- ore and, like 

 ores of that character, contained remains of recent plants. 



The Peesident remarked on the difference iu appearance of mas- 

 sive haematites from ordinary bog iron-ores and those brought by the 

 author of the paper. 



Dr. Soeby asked if it were possible that these could have been 

 deposits produced by springs, such as occur on the hill-sides of 

 Yorkshire, and are still forming. 



Mr. Paulson stated that the bog-ore deposits in Ireland occur 

 on the sides and summits of hills, and that the Rio-Tinto deposit is 

 a true bog iron-ore. 



Mr. Baueehian remarked on the resemblance between this ore 

 and that of Arklow, which is also derived from pyrites ; and con- 

 sidered that the freedom from phosphorus was to be attributed to 

 their rapid and direct formation as compared with ordinary bog 

 iron-ore, which is contaminated by accessory products of decompo- 

 sition from organisms and rock-masses. 



The Authoe, in reply to Dr. Sorby, stated that the top of the 

 deposit was regular and the bottom irregular, leading to the belief 

 that it was probably a deposit in water. Further he indicated that 

 there is an outlier on the same level. The hard cap is sometimes 

 undercut by denudation. He remarked that springs are scarce over 

 the whole district, and that there are none containing more than 

 traces of iron in solution. 



