June 1, 1864] THE TECHNOLOGIST. 



ON GRANITE AND ITS USES. 495 



B. stridula, Moon. " Bata-lee," S. — Thousands of acres are covered 

 in Ceylon with, this small "bamboo. Its stems are in great request for 

 fences, &c. 



B. nana, Roxb. — The Chinese dwarf-bamboo, of which their umbrella 

 handles are said to he made, grows about Colombo and Galle. 



ON GEANITE AND ITS USES. 



BY THE LATE PROFESSOR GEORGE WILSON. 

 NO. II. 



Special reference has been made to the enduringness of granite, and 

 the relation of that enduringness to industrial science. We are now to 

 consider this rock as very perishable, and as yielding by its decay 

 materials for important arts, and, in particular, for three — namely, the 

 arts of the glass-maker, of the potter, and of the metal-worker, of which, 

 however, I can discuss scarcely more than the first. 



With a view to understand this, let us look again at the three 

 minerals in ordinary granite. They are, as we have seen, the dark, 

 glimmering, scaly mica ; the glass-like quartz, which, when violet, we 

 call amethyst, when yellow, cairngorm or false topaz ; and the marble- 

 like felspar, which appears of so rich a red in Peterhead and Egyptian 

 granite. 



The same Hebrew poets who loved to call the mountains everlasting 

 also tell us that the " perpetual hills bow down." They do so in the 

 sense of bending their heads, in the course of ages, to the blast, and 

 wearing away under the storms of millenniums, slowly corroded by the 

 air, dissolved by the rain, ploughed by the glacier, split by the frost, 

 shivered by the lightning, and by all consumed into dust. They also 

 bow their heads in the sense of abasing themselves ; and as they 

 originally rose from the lower depths of the earth, often sink again into 

 them. Those great physical agencies which suddenly, and as it were 

 spasmodically, exerted, produce under our eyes earthquakes and vol- 

 canoes, more slowly and silently exercised, lift entire continents to 

 immense elevations, and build them up as mountain chains ; and again 

 those agencies reverse their work, and the mountain-chains are buried 

 " deeper than plummet ever sounded." But in so sinking, they are at 

 length, in the majority of cases, plunged beneath the sea, and there are,, 

 of necessity, exposed to all the wear and tear of its waves, to the ebb 

 and flow of its tides, to the fierce collision of rocks broken from them- 

 selves dashed wildly against them, to the grinding action of fragments 

 of those rocks furrowing their surfaces, to the abrading contact of sand 



