1865.] WALLACE — FLOS FEKRI. 417 



5. That water could not have flowed over the surface of the arra- 

 gonite ; for as it was found pointing in all directions, it could not 

 rise against gravity to the ends of the arborescent varieties pointing 

 upwards, which were occasionally of considerable length. 



6. Now, as the interstices of the loose rubbish had evidently at no 

 time been filled with water ; and from the position in which some of 

 the arragonite was found, it was impossible for water to flow over 

 its surface ; it therefore necessarily follows that the growth of this 

 mineral is due to a circulation of fluids through its pores. 



I may observe that after the formation of arragonite, in some 

 places water had flowed slowly over its surface and stained it with 

 various shades of the sienna-browns. In other places clay had been 

 washed over its surface ; but in both instances the arragonite was 

 more or less decomposed, and ordinary stalactitic congelations were 

 in the process of formation. 



Such were the conclusions arrived at after repeated and most 

 careful inspection of the phenomena connected with the presence of 

 arragonite in one of the Silver Band veins. 



A few months afterwards, another opportunity occurred of inves- 

 tigating the conditions connected with a cavern of greater magni- 

 tude, most splendidly lined with snow-white arragonite. 



This cavern was found near one of the principal veins of the Duf- 

 ton Pell Mine, at a depth of about 80 fathoms from the surface. 

 Flats have been formed in the Tyne Bottom Limestone in connexion 

 with this east and west vein, and these flats contained much lead-ore 

 near the outcropping of the limestone. Extensive works have been 

 made to prove this vein in the Melmerby Scar Limestone directly 

 below this rich ore-deposit. While prosecuting these works in this 

 limestone, a large joint was met with, which in some places was filled 

 with very soft rubbish, the result of decomposition ; in other places 

 it was open, and afforded pure air for the workmen, so that artificial 

 ventUation was not needed. When first discovered, it was considered 

 to be a cross vein ; but a rise made at its intersection with the east 

 and west vein proved it to be a large joint existing only in the Mel- 

 merby Scar limestone ; for it terminated altogether at the top of this 

 limestone, and no trace of it can be discovered in Eobinson's lime- 

 stone, which at this place is separated from the former only by a bed 

 of very soft and fine sandstone some 18 or 20 iuches thick. In its 

 direction northward, towards the centre of the mountains, it gradually 

 closed ; and no trace of it could be detected, though works were made 

 in its direction to an extent of 20 or 30 fathoms in the very close 

 and compact limestone. 



Excepting in the upper portion, where the arragonite was found, 

 no water trickles down the sides of this joint, nor are there any sta- 

 lactites formed, neither does it contain any of the minerals found in 

 the lead-veins of the north. A great portion of the rubbish it con- 

 tains might be due to decomposition when the joint Avas filled with 

 water ; but a portion of the very loose stuff" near the top of the joint 

 is undoubtedly the remains of limestone which had been slowly 

 decomposed by a moist atmosphere, and in consequence had fallen 



