West' Tamar District, Tasmania. 157 



absent in the enclosed pebbles), and is coloured green by 

 chrome-ochre. These ridges are between 300 and 400 feet 

 above sea-level. There are three limestone belts of some 

 importance. One is situated on the Middle Arm Creek, at 

 the Launceston track crossing, and is a white marble of fair 

 quality. Another, on the same creek and about half a mile 

 south-west of the last, is a blue or dark grey limestone with 

 calc-spar veins. Gold is said to have been found in the 

 creek here, and galena in the limestone. The third is 

 situated about three miles south-east of Douglass' (the 

 Ilfracombe ironworks), and is similar to the last. There are 

 also three iron lodes in this formation, as well as indications 

 of more. The first is at the north-east end of the Hfracombe 

 or Blue-peaked Range, and consists of a fibrous and 

 botryoidal brown hematite or limonite (kidney ore), which 

 seems to be of great extent, but has not yet been opened up. 

 An analysis of this ore in Mr. Newbery's laboratory gave — 



Ferric oxide ... 79-34 = 55-54 per cent, of metallic iron. 



Silica 15-30 



Combined water 5*16 



9980 

 EKminating the silica gives : — 



Ferric oxide ... 93-71 = 65'59 iron. 

 Water 6-09 



99-80 



Sulphur, phosphorus, and chromium were sought for, but 

 not found. 



The second lode is nearly in the centre of the same 

 range, but on its west side at Douglass'. This has been 

 worked by the Ilfracombe Co. to a small extent. 



The ore is like the last, and gave on analysis — 



Ferric oxide ... 91-14 = 63*94 per cent, metallic iron. 



Silica 2-30 



Combined water 6*20 



99-64 



Eliminating the silica gives : — 



Ferric oxide ... 93-29 = 65-30 per cent. iron. 

 Water 6-35 



99-64 



