CATARACTS, AND INUNDATIONS. 



several veins, not discernible before, of a ferruginous matter, about 

 T V of an inch thick, and when reduced to powder, it applied strongly 

 to the magnet. 



In other stones he found some veins of wood, about one and two 

 inches thick, no way petrified, though the stones were every where 

 so outwardly. Some of that woody part he also burnt in a crucible ; 

 it emitted a bluish flame, as if impregnated with sulphur, and had 

 the strong smell of burning charcoal. When burnt to a coal, and 

 reduced into powder, it faintly yielded to the magnet. 



He calcined another of these stones, weighing 1 oz. 13 dwts. 

 12^ jr. ; alter burning four hours it weighed only 1 oz. 10 dwts, 

 Sj gr. which lost 3 dwts. 4 gr. ; which proceeds probably from un r 

 petrified veins of wood in the heart of the stone, which were de. 

 stroyed by the fire, as in the crucible it emitted now and then a 

 bluish flame, like brandy when burning. This stone, when taken 

 out of the crucible, and cooled, had the colour of iron, when heated 

 in, and cooled from the forge. 



Part of another stone, which by visible veins of ore, appeared to 

 contain a sood deal of iron, he likewise calcined for four hours; 



o 



the powder yielded most surprisingly to the magnet ; so that it ap- 

 pears, that the opinion of Nennius, Boetius, and other ancieut 

 writers, was not absolutely destitute of foundation. 



The white wood-stones are generally found in the ground at 2, 

 4, 6, and 8 miles distance from the lake, and sometimes very deep 

 in the earth. The black ones are ahvays found in the water, or on 

 the shores of the lough ; sometimes at the mouths of rivers or rivu- 

 lets that empty themselves into it ; but those with wood continuous 

 liave not yet been found above twenty yards distance from the wa- 

 ter of r hc hike ; that is, where the water reaches in the winter, or 

 at other times. 



Some of these stones are outwardly covered with a thin white subu 

 ^tance, which has run through the pores of that part of the stone that 

 \va, exposed to the air, and not covered by the water, mud, or clay; 

 and on some others it is rather an incrustation of that white sub- 

 stance, v>hirh lie takes to be the slimy, unctuous, saline parts of the 

 petrescent juices that filled the outward pores of the stone, or coa- 

 gulated on it. This white part scraped, and put into a crucible in 

 a violent fire, could not be reduced to lime, though it grew red as 

 coal. This powder calcined appeared through the microscope 



