CANADIAN ROOFING SLATE. 365 



while the scow-ferry, by which the slates are conveyed to the rail- 

 way depot on the other side of the river, lies on the left. Following 

 the quarry road we ascend a steep incline all theway,which,although 

 difficult to surmount, is, as Mr. Walton remarked, a necessary feature 

 in order to have a good slate quarry. A strip of the woods has 

 been cleared on either side to allow of the access of the sun and 

 wind to dry the road. In making these clearings and construct- 

 ing the road, the proprietor expended about twelve hundred dol- 

 lars. At the end of about a mile, we come to the cluster of 

 buildings attached to the quarry, and leaving our conveyance at 

 one of the boarding houses for the employes, proceed to inspect 

 the works. 



The quarry itself is not seen from the approach, being 

 concealed by a band of serpentine which flanks the slate band on 

 the north. It was found necessary to drive a tunnel, a hundred 

 feet in length, from the slope of the hill through the serpentine* 

 in order to expose a workable face of the slate rock behind. In 

 front of the tunnel are the sheds for manufacturing the slate, and 

 a dump or spoil bank, composed of the refuse from the dr «sing 

 process. Beautiful specimens of asbestus are seen on either side 

 in passing through the tunnel, from which we emerge on the level 

 of the floor of the quarry and find ourselves in a great roofless 

 chamber, the four walls of which rise to the height of seventy feet- 

 The cleavage of the slate is about perpendicular, and runs in the 

 direction of the greatest length of the quarry. As in the best 

 quarries in other countries, the slate is found to improve in all the 

 desirable qualities in descending, and the waste, due to surface in. 

 fluences, to diminish continually. Owing to the vertical cleavage, 

 the surface influences have penetrated to an astonishing depth* 

 In the upper forty feet the rock was injured to such an extent, 

 that fully half the material quarried was wasted, and even at the- 

 present depth, the same influences are still discernible, but rapidly 

 dying out. 



At first the rock was so fissile that it could with diffi- 

 culty be split into sufficiently thick sheets, but now the plates can 

 be split to any required thickness with perfect uniformity and 

 beautifully smooth surfaces. No difficulty is to be apprehended 

 from imperfect cleavage in slate of this character, at the greatest 

 depth to which the quarry can be worked. Since it is always 

 found that in working a good band of slate the quality improves- 

 in respect to smoothness, regularity of cleavage, color and hard- 



