HERTFORDSHIRE EARTHQUAKES. 147 



" There was a hollow, obscure, rustling noise in the house, 

 which ended in a loud explosion up in the air like that of 

 a small cannon : the whole duration, from the beginning to the 

 end of the earthquake, seemed to be about four seconds of time. 

 The soldiers who were upon duty in 8t. James's Park, and others 

 who were then up, saw a blackish cloud, with considerable 

 lightning, just before the earthquake began ; it was also very 

 calm weather." 



The following account of this earthquake as felt in the valley 

 of the Lea, was communicated to the Royal Society by the 

 Rev. William Cowper, D.D., Dean of Durham : — 



" It was felt very sensibly at Northaw, and at Gubbins 

 [Gobions], the Seat of Sir Jeremy Seabrooke in that Neighbour- 

 hood, whose House was shaken very much. At a Farm, three 

 Quarters of a Mile N E of Hatfield, it was felt by the Farmer 

 and his Family, but not perceived by the Inhabitants of Hatfield 

 itself. 



" In like manner at Hertingfordbury, a Village a small Mile 

 West of Hertford, the Shock was felt distinctly ; but not 

 observed by any of the Inhabitants of Hertford. 



" At my own house at Panshanger,* two Miles West of the 

 above-mention'd Town, the Noise was heard twice, at the 

 Interval of about half a minute, resembling the Rumbling of 

 a Cart thro' the Streets ; but no Shock felt either within or 

 without-doors." 



Dean Cowper adds the following account of the Aurora 

 borealis seen between these two earthquakes : — 



" I cannot help mentioning a luminous Arch, which appear'd 

 Feb. 16 [27 n.s.] about 9 at Night. It had Arcturus in its 

 Eastern Line, which was then low in the Horizon, and extended 

 to the bright Star in the Shoulder of Orion, then bearing S W. 

 It was exceedingly bright, regular, and well-defin'd, and about 

 the breadth of the Rainbow ; which it resembled in every thing, 

 but its Variety of Colours. It continued thus for about 20 

 Minutes, declining gently Southward, and then gradually 

 separated and disappeared." 



Dr. Stukeley, in his ' Philosophy of Earthquakes,' doubtless 

 referring to one of Dean Cowper's informants, states this furt.her 

 fact with I'egard to this earthquake : " The gentleman who 

 observed it about Hertingfordbury, says, the noise preceded the 

 shock. And this is a common observation, which at once both 

 strengthens our opinion of electricity, and confutes that of 

 subterranean vapours ; for, in the latter case, the concussion 

 must precede the shock." 



\st November, 1755. 



We now come to the Great Lisbon earthquake of the 1st 

 of November, 1755, one of the most violent and widely-extended 



* The Right Hon. "William Cowper, afterwards 2iid Earl Cowper, bought the 

 Panshanger estate in 1720 ; his mother came from Durham. 



