Anniversary Address. 91 



hornblende is intermixed with these minerals. Veins of calcareous 

 spar not unfrequently pass through the rocks of this formation ; 

 and in some parts, as at Humbleton Mill, bright yellow crystals 

 of sulphuret of iron have deluded the discoverers into the hope, 

 that a Cheviot gold-mine was sparkling before their eyes. The 

 porphyry terminates a little below Humbleton Mill. 



" The carboniferous sandstone is seen on the banks of Wooler 

 Water and at Wooler-haugh ; it is fine-grained, rather soft, and 

 of a reddish hue. It also forms the high grounds ranging along 

 by Whitsun-bank towards the Till. At Wooler this sandstone 

 is covered over with an accumulation of sand, clay and gravel. 

 A section of these superficial deposits is exposed in Humbleton 

 burn, where it consists of a deposit of gravel or small pebbles 

 of porphyry, 6 feet; and a lower mass of sand and clay in which 

 are imbedded large blocks of the red sandstone, with a few por- 

 phyry blocks, 20 feet. Sandstone blocks are not seen in the 

 superficial covering over the porphyry. The facts noticed accord 

 with what we have elsewhere remarked regarding the boulder 

 formation of Northumberland — it has chiefly been derived from 

 the breaking up of the rocks of the district ; far-travelled blocks 

 are the exception — not the rule. 



" Nearly one mile west of Wooler, on the summit of Kettle- 

 hill, we found a large Roman camp of quadrangular form and 

 having four Valiums on the north. It is called Greenside Camp, 

 and sometimes Cauterdale. The hill rising steeply on all sides,' 

 the position must have been exceedingly strong. It commands 

 an extensive prospect ; all the prominent objects to the east and 

 south being visible from it. Roman coins and a broken sword 

 were found here some years ago. On the south extremity masses 

 of porphyry are exposed in a cliff, which formerly bore a rude re- 

 semblance to a chair ; it is now called l The King's Chair ; ' and 

 tradition says that a king sat hereon, and, through an opening 

 in the hills, beheld a battle fought on the lower grounds to the 

 south. 



" On the north side of Humbleton burn is a conical hill trun- 

 cated at the top, and rising abruptly about 100 feet above the 

 level of the burn; the slope, though considerable, is less steep on 

 the other sides. This was one of the strongholds of the ancient 

 Britons. A rampier (now obliterated) ran around that part of the 

 hill not protected by the ravine of the burn. The summit of the 



