A GOLD MINE. 65 



must slant more and more till they are flat, and 

 then begin to be piled up to make another book 

 ledge. At the point where the rocks or strata 

 are perpendicular it is termed an anteclinal ; at 

 the point where they have flattened out it is 

 termed a synclinal. Now from one of these 

 antecliuals to another the distance is generally 

 several miles. The ledges or strata are all of 

 two varieties quartzite and slate ; they rest 

 against each other in alternating layers, perhaps 

 of a few feet, or many feet, or a few inches in 

 width. Both of these kinds of rocks are of 

 shore origin; they are sediments and sands 

 ground up on a seashore many million years 

 ago ; there can be no proper question as to this 

 statement. Now supposing that all the region 

 is bare, we would see white lines running along 

 between the layers of rocks ; examination would 

 show that they were veins of hard rock, varying 

 in width from a mere line to five feet, and run- 

 ning easterly and westerly with the ledges in 

 which they are enclosed. If you will put leaves 

 of paper and pasteboard between the books I 

 have imagined to be piled up, then these will 

 show the positions of the veins in the rocks. 

 Then you will see that some veins will be per- 

 pendicular and others more or less slanting; 

 these are called "regular" veins, or interstrati- 



