64 The, Causes and Phenomena of Earthquakes. 



28th of July, and as no steamer had recently passed, we con- 

 sidered it an anomalous occurrence, without forming any posi- 

 tive conclusion respecting it. But I feel assured it had little to 

 do with a steamer. 



I will now quote a few cases of parallel disturbances from 

 Perrey's Earthquake catalogues, where it is expressly stated that 

 no shock was noticed : — 



" On the 18th September, 1763, the sea suddenly rose ten feet 

 at Weymouth, in Dorsetshire, and fell back as suddenly. 



" On 28th November 1767, the tide at London ebbed and flowed 

 twice in an hour and a half. 



" On 6th September, 1785, an extraordinary rising of the sea 

 took place at Rochelle, in France. 



" On 11th September, 1787, the Lake of Lugano, in Italy, was 

 violently agitated ; there was a violent wind at the time. 



" On 4th July 1809, <m extraordinary flux and reflux of the 

 sea in the G-enoese territory took place, at intervals of a quarter, 

 half, one hour. On the same day a similar fact was recorded 

 near Lisbon, and on the 27th of that month at Naples. 



" On 3rd January, 1824, the sea rose and fell unusually at 

 Copenhagen, in Denmark." 



It must be admitted, however, that shocks have been recorded 

 as taking place in the neighbourhood of many similar disturb- 

 ances of the seas and rivers, and of one of them that of Pesaro, 

 in the Pontifical States, on 18th March, 1826, it is said, " the 

 sand, mixed with the water, destroyed its transparency to the 

 distance of two miles from the shore " at Sinagaglia. 



The amount of disturbance in August last was so great, and so 

 generally comparatively equal at different places, along a coast 

 line extending through fully 2800 miles, that its source must 

 have been at a considerable depth. 



Yet, at first, it was admissible that as the storm and sudden 

 violent gale of the 19th of August followed it, the oscillations 

 might be due to a coming Cyclone ; it may illustrate such an 

 effect to quote an example or two. 



In the year 1831, a violent swell of this kind broke on. the 

 Bermudas, having been produced by a hurricane in Barbados, 

 more than 1000 miles distant. So on 30th January, 1845, the 

 Eurydice frigate was endangered at anchor in St. John's Bay, 

 Antigua, by the swell raised by a storm at Bermuda, quite as far 

 off. Colonel Beid was at Bermuda during the hurricane of 1839, 

 and noted the sea breaking loudly on the south shore, full three 

 days before the storm reached the same locality, and the hurri- 

 cane was then nearly 700 miles off. 



As the storm passed, the south shore became quiet, whilst the 

 north received the impetus of the swell progressing to New- 

 foundland. This author points out how the muddy appearance 



