()5'2 PHILOSOPHICAL TRANSACTIONS. [aNNO J 755, 



12. In Oxfordshire, at Shirburn Castle, the Seat of the Earl of Macclesfield, 



Pres. R. S. Communicated by his Son, the Lord discount Parker, F. R. S. 



then on the Spot. p. 368. 



On Saturday November 1, a little after 10 o'clock in the forenoon, walking in 

 the garden at Shirburn castle, he perceived the gardener, who was coming to- 

 wards him by the end of the moat, on a sudden stop short, and look earnestly into 

 the water. He went towards him, and perceived immediately a very strange mo- 

 tion in the water. There was a pretty thick fog, not a breath of air, and the 

 surface of the water all over the moat was as smooth as a looking-glass; yet in 

 that comer of the moat near which he stood, the water flowed into the shore, 

 and retired again successively, in a surprising manner. The flux and reflux were 

 quite regular. Every flood began gently; its velocity increased by degrees, till 

 at last, with great impetuosity, it rushed in till it had reached its full height, at 

 which it remained for a little while, and then again retired, at first gently ebb- 

 ng, at last sinking away with such quickness, that it left a considerable quantity 

 of water entangled among the pebbles, laid to defend the bank, which run 

 thence in little streams over the shore, now deserted by the water, which at other 

 times always covers it. As the slope of the sides of the moat is very gentle, the 

 space left by the water at its reflux was considerable, though the difference be- 

 tween the highest flood and lowest ebb of these little tides, was but about 4-i- 

 inches perpendicular height; the whole body of water seeming to be violently 

 thrown against the bank, and then retiring again, while the surface of the whole 

 moat all the time continued quite smooth, without even the least wrinkle of a 

 wave. He sent persons to several other ponds, in all which the agitation was 

 very considerable. The swells, that succeeded each other, were not equal, nor 

 did they increase or diminish gradually; for sometimes, after a very great swdl, 

 the next 2 or 3 would be small, and then again would come a very large one, 

 followed by 1 or 2 more as large, and then less again. 



13. In Devonshire and Cornwall, at Plymouth, Mounts-Bay, Penzance, &c. 

 By John Huxham, M. D., F. R. S. p. 371. 



Saturday, November 1, about 4 p.m. we had (just about high water) an ex- 

 traordinary boar, as the sailors call it. The sea seemed disturbed about 20 mi- 

 nutes before, though there was very little wind that day, or for some days before. 

 One of our surgeons, who had then just crossed the ferry at Creston, a mile to 

 the south-east of Plymouth, said, that the tide had made a very extraordinary 

 out (or recess) almost immediately after high water (about 4 p. m.) left both the 

 passage-boats, with some horses, and several persons, at once quite dry in the 

 mud, though the minute or two before, in 4 or 5 feet water; in less than 8 

 •minutes the tide returned with the utmost rapidity, and floated both the boats 

 again, so that they had near 6 feet water. The sea sunk and swelled, though in 



