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generally in every direction, but for the most part at a considerable 

 angle both to the perpendicular and horizontal. Certain peculiar ar- 

 rangements of these veins are, however, noted in certain 

 areas, as at the King Bros.' mine in Ireland, where the 

 serpentine appears to be regularly stratified almost in 

 the manner of sandstone or quartzite in layers dipping to the north- 

 west, and the veins of asbestus apparently follow what, in sedimentary 

 rocks, would be regarded as the bedding planes. In several other 

 places the veins, few in number, cut the rock in an almost horizontal 

 position, and when found in a knoll can be traced across from one side 

 of the hill to the other nearly on the same plane, but as a rule the vein& 

 are irregularly placed. In size they range from mere threads up to a. 

 thickness of five or six inches, though the most of the workable veins in 

 the principal mines do not, or but rarely, exceed two and a half inches in 

 width or length of fibre, and such veins, where the asbestus is of good 

 quality and unbroken by partings of iron, are regarded as extra No. 1 

 material. There are, however, generally more small veins of one inch 

 or less than of the larger size. Serpentines associated with talc or with 

 soapstone, where the latter is in quantity, rarely appear to carry veins 

 oi asbestus to any extent, and such steatitic rock is not usually con- 

 sidered good mining ground. The Broughton mine may possibly be 

 cited as an exception to this principle, since at this place a vein 

 of large size of very fine fibre was found lying between serpentine and 

 soapstone walls. As the soapstone became more abundant, however, 

 the size of the vein rapidly became less and finally split up into small 

 strings and became useless, and it is a fact worthy of note that at the 

 great and profitable mines in Thetford and at Black Lake soapstone is 

 absent from the rock mass. 



As for the origin of these veins in the serpentine several theories 

 have been advanced. In composition the vein matter is, as already 

 mentioned, apparently the same as the containing rock, and the chryso- 

 tile is simply a fibrous serpentine. Some have supposed the veins 

 to be formed when the mass of the rock was in a pasty state and 

 exposed to sundry strains or twistings which produced the fibrous 

 nature of certain portions. That the rocks have been exposed to 

 such violent action is very evident from their present faulted character. 



