610 MR MILNE ON A REMARKABLE OSCILLATION OF THE SEA. 



FACTS OBSERVED. I. The following are the places, where I have ascertained that the phenomenon 

 was observed on the 5th July ; and in mentioning each place, I shall notice the 

 most material circumstances attending it which occurred there : 



At Newlyn, in Mountsbay, Cornwall, at noon, about an hour and a half after high 

 water, the sea suddenly retired to the depth of 3 or 4 feet, rushing out 

 to the distance of at least half a mile. It then returned, in the same state 

 of agitation, to its former level. The time occupied in each of these move- 

 ments, was ten or fifteen minutes. 



This ebbing and flowing was observed four times ; the duration of each 

 movement being throughout nearly the same. 



The current produced by the flux and reflux, was about three miles an 

 hour. 



At Penzance, Cornwall, about ll h 30' A.M., three currents were observed flow- 

 ing parallel to one another, in opposite directions, and running at the rate of 

 four or five knots an hour. The agitation increased from noon till half-past 

 12, and at 1 p. M. its violence was not diminished. 



At Marazion, three miles east of Penzance, one of the influxes was observed 

 about one o'clock. The sea then rushed in from the south to the depth of 

 4 or 5 feet, and from the distance of about 50 yards, and almost immediately 

 after retired to its previous level, occupying about ten minutes in each move- 

 ment. Between 2 and 3 P.M., and after the tide had entirely left the 

 causeway at Marazion, the sea returned and covered the central parts of it. 



At each of the piers of Mousehole, Nervtyn, the Mount, and Portleven, a most 

 violent eddying current was observed for two or three hours, so remarkable 

 as to arrest the attention of all, and such as had not occurred during the last 

 fifty years. The boats were whirled about by it, in all directions. The ver- 

 tical height to which the sea rose and fell at those piers, was from 2 to 4 feet, 

 and each retreat and advance respectively occupied about 10 or 15 minutes. ' 



At Plymouth, the oscillation was observed a little earlier in the day. Captain 

 WALKER, R.N., the intelligent harbour-master there, writes to me, " I happened 

 to be standing on the pier, at the entrance of Sutton Pool, I think about 11 

 o'clock, a little after high water. My people were in the boat at the entrance 

 of the Pool, which is about 90 feet wide. I noticed, that all at once, the water 

 ran out of the Pool, carrying my boat and others along with it, and in a 

 minute or two, it had again ceased to ebb. My coxwain, who was in my 

 boat, tells me, that the water first ran into the Pool, carrying a barge and 

 boats along with it, and again ran out faster than it ran in." 



At Dunbar, at the mouth of the Firth of Forth, the phenomenon was observed 

 about 6 P.M., or rather later. The sea was observed to flow up in the first 



1 The notices here given in regard to Mountsbay, are abbreviated from an account which appeared 

 in the Literary Gazette of 15th July 1843. 



