290 THE GEOLOGY OF THE LABRADOR COAST. 



very prominent island near " Indian Tickle," a harbor at 

 the northern side of Hamilton Inlet. Here are some- 

 remarkable dykes which ascend the gneiss hills in huge 

 irregular zigzag crests, often crossing each other at right 

 angles. 



Beyond this point the older Laurentian gneiss again 

 appears, and forms the high bold shores extending to- 

 Hopedale, rising in the interior into lofty imposing 

 mountains on whose tops lie patches of snow. 



Among the erratic rocks at Domino Harbor were 

 some which show that in the interior are beds of jasper 

 and chert. There occurred several small bowlders of jas- 

 per and gneiss. The jasper was pale green, banded and 

 striped by darker shades of green, while the irregularly- 

 alternating bands of syenitic gneiss appeared to be an 

 altered quartzite, as it was found under a glass to be 

 largely composed of a fine granular quartz-rock, with a 

 little flesh-colored and white feldspar, and minute par- 

 ticles of hypersthene. • 



Several bowlders of chert occurred at Tub Island. 

 This was a very tough, compact, silicious rock, lineated by 

 fine veins of quartz. It weathers to a dull chalky white. 



It is most probable that these rolled stones were borne 

 down from the interior by glaciers, but the chert pebbles 

 may have been borne on floating ice from Frobisher's 

 Bay, as Mr. Hall notices such rocks as being abundant 

 there. At Tub Island I was shown specimens of mag- 

 netic iron ore, which were brought from " Cartwright's 

 Tickle," a few miles toward the main land. It occurred 

 in veins half an inch wide.* 



* For further information regarding the Laurentian rocks of Northern Labra- 

 dor, see Dr. Bell's observations in Report of the Canadian Geological Survey 

 for 1884 and '85. 



