128 MR. E. W. BINNEY ON A VEIN OF LEAD 



those near the veins of barytes at Grimshaw Delph — show 

 no traces of the action of heat ; the joints of the stone and 

 shale near the sides of the vein have a httle more vertical 

 cleavage than those rocks have at a distance from it, but 

 that is the only difference which appears. In the 18 inches 

 seam, the lead goes through the coal without in any degree 

 affecting it ; for the latter is just as bright and bituminous 

 there as it is in any other part of the seam, and appears to be 

 in no way altered by being in contact with the former. I ex- 

 amined the vein chiefly in the vicinity of the 18 inch coal. 

 This bed appears to me to be identical with the Gannister 

 coal of Rochdale. It has a hard burr floor, which differs in 

 some degree from the usual Gannister, and a black shale 

 roof. In the latter is an abundance of Avicula papyraceus, 

 Goniatites Listen, an OrtJwceras, and a Posidonia mixed 

 with many scales of ganoid fishes, amongst which is the 

 Megalicldhys Hibherti. The walls of the vein, as before 

 stated, were but httle altered, and very few portions of them 

 had fallen into the fissure, so generally the case with rake 

 veins. 



The main features of this vein of lead are the following ; 

 namely, the freedom of the metal from vein stuff, and the 

 bright condition of the coal found in contact with the 

 lead. 



The firet fact would seem to indicate, that the solution 

 from which the sulphuret of lead was precipitated, had 

 been far purer and freer from other salts than is generally 

 the case with veins of sulphuret of lead, either in carboni- 

 ferous or limestone districts. The lead found in the coal 

 measures at Anglezark, is enclosed in a mass of sulphate of 

 barytes ; and most of the veins of lead in the limestone 

 districts of Derbyshire, are generally enclosed betwixt walls 

 of carbonate of lime, fluor spar, or sulphate of barytes, whilst 

 those found in slate and silurian deposits are generally ac- 

 companied by quartz. The veins in red marls and clays, 



