248 



GEOLOGY OF THE SECOND DISTRICT. 



tions, as has already been observed, were made down to tlie ore, on four transverse lines, 

 and one in the direction of the length of the vein. These excavations were made sufficiently 

 large to admit of a thorough examination, whether of rock or ore ; and specimens were taken 

 from each, and labelled and niimbered on the spot, to prevent any mistake. By pursuing 

 this course, I obtained the result which will be given in the proper place. As to the actual 

 width, I give only that which was obtained by measuring along the line of excavation, which 

 was made at right angles to the vein ; but it is far from being certain that the western limit 

 of the vein was ascertained, as in proceeding west, the accumulation of soil increased rapidly, 

 and the examinations were therefore discontinued in that direction. It is not, therefore, at 

 all certain that I have stated the actual width of the Sanford vein. 



By the course described above, the width of the ore on the main line of excavation is 514 

 feet; and the length, along a line nearly in the centre of the vein, 1,667 feet: it then passes 

 beneath tabular masses of rock. Having given the width and length of that portion which 

 has been actually examined, it is proper to state, that the vein disappears by passing under 

 or beneath the rock at both sides ; that it is not discontinued, is proved by excavation at 

 numerous places at the northern and southern extremities, where it may be seen passing 

 beneath tabular masses of the hypersthene rock. The shape of the vein which has been 

 exposed, is nearly triangular. The annexed diagram will explain the nature of the observa- 

 tions which are recorded in the following pages : 



67. 



«, Middle section ; b and c, two parallel sections south ; J, section north ; e, longitudinal section. 



