VOL, XLIX.] PHILOSOPHICAL TRANSACTIONS. 653 



a much less degree, for near half an hour longer. It was said, that at the next 

 morning's tide there were several very large surges. This boar drove several ships 

 from their moorings, and broke some of the hawsers, and twirled the ships and 

 vessels round in a very odd manner. At Crunill-passage, over another arm of 

 the sea, about 2 miles west of Plymouth, the same phenomena were obser\'ed; 

 and in Stone-house lake, that communicates with that arm of the sea, the boar 

 came in with such impetuosity, that it drove every thing before it, tearing up the 

 mud, sand, and banks, in a very shocking manner, and broke a large cable, by 

 which the foot passage boat is drawn from side to side of the lake. 



You will please to observe, that it happened not here till about 4 p.m.; at 

 Portsmouth, about 1 J a. m.; in Holland about 11 a. m.; at Kinsale, &c. in Ire- 

 land not till 3 or 4 p. m. 



14. On the Coast of Cornwall. By the Rev. fVilliam Borlase, of Ludgvan, 



A.M.,F.R.S. p. 373. 



A little after 1 o'clock in the afternoon, about half an hour after ebb, the sea 

 was observed at the Mounts-bay pier to advance suddenly from the eastward. It 

 continued to swell and rise for the space of 10 minutes; it then began to retire, 

 running to the west and south-west, with a rapidity equal to that of a mill- 

 stream descending to an undershot-wheel ; it ran so for about 1 minutes, till 

 the water was 6 feet lower than when it began to retire. The sea then began to 

 return, and in 10 minutes it was at the before-mentioned extraordinary height; 

 in 10 minutes more it was sunk as before; and so it continued alternately to rise 

 and fall between 5 and 6 feet, in the same space of time. The 1st and 2d fluxes 

 and refluxes were not so violent at the Mount pier as the 3d and 4th, when the 

 sea was rapid beyond expression, and the alterations continued in their full fury 

 for 2 hours ; they then grew fainter gradually, and the whole commotion ceased 

 about low water, 5\ hours after it began. 



Penzance pier lies 3 miles west of the Mount, and the reflux was first observed 

 there 45 minutes after 2; the influx came on from the south-east, and south- 

 south-east. Here the greatest rise was 8 feet, and the greatest violence of the 

 agitation about 3 o'clock. Newlyn pier lies a mile west of Penzance. Here the 

 flux was observed first, ss at the Mount, and came in from the southward (the 

 eastern current being quite spent) nearly at the same time as at the Mount and 

 Penzance, but in a manner somewhat different; it came on like a surge, or high 

 crested wave, with a surprising noise. The first agitations were as violent as any ; 

 and after a few advances and retreats at their greatest violence, in the same space 

 of time as at the Mount, the sea became gradually quiet, after it had risen 10 

 feet perpendicular at least. This is near 6 feet more than at the Mount pier, 

 and 2 feet more than at Penzance. The agitations of the sea at Moushole, an- 

 other pier in this bay, did not materially differ from those at Newlyn. 



