322 Mr. J. S. Enys's Remarks on the Granite found, 



of the granite, varying in size from 10 to 500 tons, or loose 

 rocks of equal size ; many of these last, however, are pro- 

 bably in their original position, if any judgement can be form- 

 ed from the coincidence both of the remains of the natural 

 joints and of the " cleaving line," with the quarry masses : such 

 seems the case with the Main Rock or Tolmen, a remarkable 

 and well-known rock, situated near the centre of the hard 

 granite line; it is supported on several large rocks by two 

 points, and measures about 500 tons. 



Granite is always measured, and 14 cubic feet are allowed 

 to a ton; though 1 3j of fine grit will generally amount to 

 that weight. 



Cleaving is used to express splitting up a rock into blocks 

 for sale. 



The joints both of the hard and softer granite are very simi- 

 lar, but are more frequent and numerous in the latter variety. 

 They have a strong tendency to meet at right angles, so as to 

 form masses or rocks of a rectangular shape ; these are often 

 50 feet long, and from 10 to 25 feet deep, and seem exactly 

 similar to those at the Land's End and Cape Cornwall, and to 

 the Logan Rock. 



A small quantity of a softer stone is occasionally found be- 

 tween some of the joints, which is not observed to be present 

 in exposed headlands. The Arris is likewise square, but on 

 rocks long exposed to the influence of the weather it seems 

 to have been rounded. The rectangular form, however, is as 

 strongly marked as in the quarry, the joints of which are ge- 

 nerally visible, though the granite seems in most instances to 

 be in actual contact. Occasionally a rock has been split within 

 two inches of a joint, which has only been foundry the break- 

 ing of the blocks in working. One of these joints is nearly 

 horizontal, and is called the Bed-way or Floor, and two are 

 nearly perpendicular, one of which is found generally to run in 

 a direction N.N.W. and S.S.E. with a variation of 15 or 20 

 degrees either way ; the third being across. In some quarries 

 this arrangement is extremely regular, though in others many 

 of the joints are " unconformable." Fortunately, blocks for 

 buildings are mostly required of rectangular forms, so that 

 rocks are often split up to great advantage. 



To form a cubic block, it is evident three ways of cleaving 

 are required : these are termed by the cleavers or stone-cutters, 



1st, Capping or Quartering: 



This is a line parallel to the horizontal bed-way or floor. 

 Capping is the term used for splitting off the top of a rock in 

 its natural position, or of a block split off" which lies as when 

 found in the quarry. Quartering is the term when the block 



