364 MINERALOGY. 



Mineralogy of and Into some of these we rowed for several hundred 

 Shetland. feet. Soon after, we land, and find a (jompact limestone, 



interspersed with veins, or reddish calcareous spar, to 

 succeed the sandstone. As we advanced, the hills on our 

 right became higher, and were composed of micaceous 

 schistus, especially at Coningsburgh. From this point 

 they gradually fell in height, and isandstone of a dif ty 

 brown colour succeeded. 

 ' At Sandlodge, in 1803, (when I was there), a cop- 



' per-mine was wrought, which has, I understand, been 

 since given up, but which, I have been told, it is in con- 

 templation soon again to open. There was then a small 

 but well-constructed steam-engine on it. The principal 

 shaft was sunk within a few fathoms of the sea. The 

 miners had penetrated to the depth of about twenty-two 

 fathoms, and were but little incommoded with water. 

 The upper rock was sandstone ; and below it, at twenty- 

 two fathoms, lay a petrosiliceous, or perhaps quartzy 

 rock, traversed by many veins of brown quartz. This 

 was the greatest depth to which they had then penetrated; 

 and I believe that the hardness and unpromising nature 

 of this rock, was the cause of their so quickly giving up. 

 At that time, there were but two Cornish miners, besides 

 a Cornish Captain of the Mines, engaged, and theso 

 were chiefly occupied in giving directions to the natives 

 employed to work in the mine. The want of men suf- 

 ficiently skilled in mining, was certainly one cause of 

 their failure. The principal manager was a partner, who 

 had chiefly directed his attention to the corn-trade, as I 

 was informed, and who was totally ignorant of the art of 

 mining. The principal lode or vein lies between the 

 sandstone and the petrosiliceous rock, in a direction from 

 N. E. to S. W. The copper-ore is chiefly green carbo- 

 nate, and the sulphuret; it is imbedded in an iron-ore, 

 which is sometimes pulverulent, and was called by the 

 Cornish miners gozzan. The iron-ore is by much the 

 most abundant. When Mr. Jameson visited this place, 

 the copper-mine was not opened ; and he only mentions 

 iron-ores as the product of the mine, which many years 

 ftgo had been wrought by an English iron company, but 

 pifterwards abandoned. It was subsequent to Mr. Jarae«, 



soil's 



