﻿36 Mr. R. Edmonds on Extraordinary Agitations 



respectively lower and higher than on any other day of the year 

 up to June. The maximum of the thermometer at Plymouth 

 this day was 74°, the minimum of the preceding night 44°, 

 showing a range of 30°, whilst at Penzance the contemporaneous 

 range was only 15°. The weather at Plymouth this forenoon 

 was very foggy, and of such an unusual character that on going 

 out of doors into the street I felt as if entering a hothouse. The 

 above readings of the barometer and thermometer are from the 

 registers kept at Penzance by Mr. Richards, and at Plymouth 

 by Mr. Merrifield. 



On the following morning, the 7th of May, at the Plymouth 

 Great Western Docks, when the gatekeeper went to close the 

 gates at high water about 7.30, he observed to his surprise an 

 extraordinary current rushing through them into the dock, and 

 rising to the perpendicular height of one foot above the proper 

 level of the tide at that time. When it ceased he immediately 

 closed the gates, and did not wait to see if it were succeeded by 

 other such currents. The thermometer this day in Plymouth 

 was 78°, the maximum of the year up to the 11th of June. 



I have, in my last paper (read before the Society in 1865*), 

 described a similar but much greater disturbance of the sea in 

 Mount's Bay and Plymouth on the 14th of October, 1862, and 

 have therein referred to those of the 31st of May and 8th of June, 

 1811, 5th of July and 30th of October, 1843, 23rd of May, 

 1847, and the 25th-26th of June and the 4th of October, 

 1859 — which also occurred contemporaneously in those places, 

 and which I had previously describedf, together with the accom- 

 panying states of the atmosphere. 



The only simultaneous disturbance of the sea of this nature 

 in Mount's Bay and Plymouth during the last century which I 

 can find recorded besides those on the days of the two great 

 earthquakes of Lisbon, is that of the 28th of July, 1761, when 

 the sea in Mount's Bay rose six feet above its proper level. 

 Borlase, after having described it, states that there was "thunder 

 at times all the day," and at 8 p.m. the church of Ludgvan, of 

 which he was the rector, was struck by lightning J. 



Thus have all the recorded extraordinary agitations of the sea 

 in Mount's Bay and Plymouth, except those on the days of the 

 two great earthquakes of Lisbon, which they perfectly and in all 

 respects resembled, been accompanied with thunderstorms or 

 great maxima of the thermometer or considerable minima of the 

 barometer. And because they are always, or almost always, 



* This paper appeared in the Philosophical Magazine for January 

 1866, pp. 45-52. 



t See my former papers in the ' Transactions ' of the Society, and my 

 'Land's End District/ p. 101. 



% Phil. Trans, vol. lii. p. 507. 



