614 MR MILNE ON A REMARKABLE OSCILLATION OF THE SEA. 



denly left dry ; as suddenly, in a little afterwards, the sea returned, and it 

 was with difficulty that the boats were preserved." 



" The same phenomenon appears to have occurred all along the east coast of 

 Shetland, from Unst to Dunrossness, and to have continued for several hours. 

 Its occurrence on the west coast on this day, I have not ascertained. The 

 day was remarkably fine ; there was scarcely any wind ; it was rather 

 cloudy." 



" The fishing-boats, on the commencement of the oscillation, fled to land, with 

 all possible speed, fearing some unheard-of judgment to be at hand. Thomas 

 Stone, carpenter, Lerwick, was on board a vessel, a short distance from the 

 shore. He says that the appearance and action of the water he can scarcely 

 describe. The feelings produced on his mind, were such as might be on the 

 dissolution of nature." 



" A similar phenomenon occurred on the west side of Shetland some years ago, 

 attended with loud thunder." 



The report from Mr LAWRENCE at Boddam, Dunrossness (Shetland), is as fol- 

 lows : " On the 7th July, between 2 and 3 P.M., I was standing at the sea- 

 side, observing a boat hauling out to sea. I was astonished to observe her 

 suddenly get aground, and then in a few minutes float again. This occurred 

 three times in the course of half an hour. I marked it particularly, being 

 surprised to see the pool in which the boat was, filled and emptied three 

 times successively, by the action and reaction of the tide." 



On the 8th July, the oscillation was, so far as I know, observed only 

 At Cullercoats, near Tynemouth, on the coast of Northumberland. The sea, at 

 10 A.M., was in a state of perfect smoothness. There was not the slightest 

 wind which could ruffle the surface. The tide had then flowed about half 

 way, when suddenly the sea receded to a distance of about 12 yards. After 

 remaining in this state for about two minutes, the tide then as suddenly 

 flowed again to the distance of about 2 feet, beyond the previous and regular 

 water mark. The tide thereafter flowed on, in its natural course, without 

 farther interference. The whole disturbance occupied ten minutes. 



Whilst the above are the only places where the sea was observed and watched 

 when in a state of oscillation, or alternate flux and reflux, there are some other 

 places where the tide registers indicate a disturbance in the ordinary flow of the 

 tides. 



At Bristol, where there is a very complete and accurate self-registering tide- 

 gauge, the tidal curve, as traced by the instrument, of which Mr BUNT has 

 kindly sent me a copy, exhibits, about 2 P.M. on the 5th July, several devia- 

 tions, indicating, first a fall, then a rise, and next a fall, of the oceanic waters 



