116 Mr. William Phillips on the Veins of Cornwall, 



Width of Veins, 



The East and West, or metalliferous veins, are generally from 

 one to three feet in width, but vary to 30 feet. In the old work- 

 ings of Relistian mine for tin, there are chasms, both open to day* 

 and underground, full 30 feet wide. A vein from one to three feet 

 in width is preferred, because, though many instances of the con- 

 trary have occurred, it is found that the product is generally as 

 good as in wider veins, on account of there being, for the most 

 part, less admixture of foreign substances with the ore. 



A vein sometimes varies in width in the same mine very materi- 

 ally, and is often found to increase in that respect in going down. 

 One of the lodes in Huel Alfred % varies from 9 to 24 feet : there 

 is a peculiarity in its direction which is noticed in speaking of that 

 description of irregular veins called Contres. As opposed how- 

 ever to the width of that vein, those of Herland and Drannack and 

 Prince George mines, which are separated from Huel Alfred only 

 by a brook and a cross vein, may be cited. There, instead of con- 

 tinuous veins of a somewhat irregular width, they are remarkably 

 small, most of them varying only from 2 to 6 inches in the widest 

 part, which was about the middle, and going away East and West 

 in mere strings. A tin vein in Whealan Coates mine, not 3 inches 

 wide, was very rich, and found to be worth working. 



If in working on the course of a vein, or in sinking through the 

 load, the country is found to assume a greater hardness in a very 

 considerable degree, the vein generally becomes narrower. 



* Ore is said to be discoyered near the Jay, when it lies near the surface. 



:J: Huel signifies a Mine, according to the Cornish. Engliih Vocabulaiy of Borlass. 

 It is commonly, though erroneously spelt, Wheal. 



