70 PHILOSOPHICAL TRANSACTIONS. [aNNO 1713. 



ing a hideous dull noise raised their curiosity ; and they observed that the whole 

 space ABCD containing about 3 Irish, or 4^ English acres, had been all day in a 

 gentle motion; and the noise continued all night, occasioned by the rubbing of 

 bushes, tearing of roots, rending and tumbling of earth. The motion ceased 

 on Wednesday afternoon, when they saw the bushes on the bank ef were re- 

 moved, some standing and some overthrown, to the plain meadow yy. The 

 green ground above ef, when it came to the top of the steep part ef, rent with 

 hideous chasms, 10, 15, or 20 feet deep, and tumbled down in rolls of a yard 

 or two thick, and 10 or 20 long and broad, not unlike a smooth water breaking 

 over a cataract, and tumbling in waves below. , 



There was a precipice at the top xx, 65 feet perpendicular, making the slope 

 line XX, 126 feet. The ground from x to l, was made more level, the whole 

 perpendicular height of x not exceeding the plain of l, above 30 feet : but the 

 ground at l, in the whole line from e to f, was mounted above 20 feet higher 

 than the unmoved ground on either side, at e and f ; and the height of l, above 

 the plain of y, is 55 feet. There was a ditch hi, went across the ground, which 

 being broken off at oo, is removed, together with the moving part, 34 feet 

 lower down than the immoveable; but at the bottom y, it is tumbled 6o feet 

 over the plain meadow. The breadth at the bottom ab is 400 feet, and at cd 

 about 300. 



The whole face of the precipice xx, is of a blue clay, mixed with many little 

 blue stones. The metal is very hard when dry ; but on any rain it softens to a 

 kind of mortar, without the degree of toughness and stiffness that is natural to 

 clays. It is very much like that gravel or sand, which is somewhat of a grey 

 marly nature, and with which of late they so much improve the ploughed land 

 in this country. About x there are chasms or gapings, full of water, which 

 make a rill down the hiatus bea, but in no greater quantity than might have 

 been expected from a well sunk to a less depth. Though I was told that there 

 were holes in the higher mountains, that received water under ground; yet I 

 can find no such thing, nor any symptoms of a current under ground, either 

 where it enters or rises, in all the neighbouring ground for some miles. It 

 seems to me that there has been no vacuity under ground, to receive the sub- 

 siding earth; for what the bank elf is raised higher, and what is tumbled down 

 to the plain ab, may very well compensate the subsiding at the precipice xx. It 

 is to be observed, that before the rupture, the declivity from x to l, was not 

 altogether uniform, but was hollower where x is now, than the adjacent parts; 

 it might have been 10 feet deep in the middle, and 100 feet diameter; and they 

 have a tradition, that this was made by a subsiding before the 41 wars, the 

 oldest epocha the country Irish know of. 



