406 
NATURE 

overcast during the evening, suddenly cleared up towards II P.M., 
but was again completely covered at 11.15. The barometer was 
heaving during the night, but no special disturbance is registered 
on the photographic curve; the corrected reading at If P.M. 
was 29°$87, and 29°$85 at 11" 11". j 
The rise of temperature was rather sudden just before the 
passage of the earth-wave, attaining its maximum, 43°4 at 
115 11™, the wet bulb being then 42°4”. 
For most of the afternoon the wind was W.S.W., and was 
changing from W.N.W. toS.W. between II P.M. and midnight ; 
at the time of the shock it was due W. It was blowing gently 
at the average rate of some thirteen miles an hour from. the 
previous midday, and at scarcely four per hour after midnight. 
At 10 P.M. its velocity was nine miles an hour. 
The trace on the magnetic declination curve shows that the 
magnet was moving rather rapidly from W. to N. when the 
shock occurred, and a slight irregular movement at 115 14 may 
be due to the earthquake. The magnets were very quiet before 
10 P.M., and disturbed from 10 until morning. ‘ : 
The shock was felt very generally throughout the neighbouring 
villages. 
The sound is generally described as that of a strong gust of 
wind, followed by a noise resembling the passage of an express 
train over a wooden bridge. This was followed by a very dis- 
tinct rocking of the furniture, beds, and walls ; the whole of the 
houses seemed to shake violently, and the floors to rise ; the 
rooms swayed backwards and forwards several times. — The 
motion was violent enough to awaken persons from their first 
sleep. Many thought that part of the building had fallen in, or 
that something heavy had tumbled down in a room over-head. 
The rushing sound and crash were followed by a rumbling noise. 
The motion appeared to begin suddenly, to grow stronger for a 
time, and then to die away. It was more regular and powerful 
than the shaking from a heavy waggon in the houses of an old 
street. 
The time the whole disturbances lasted is generally estimated 
at about half a minute; but this, I should be inclined to think, 
is excessive. 
The direction of the motion is supposed by most to have been 
from E. to W. ; S. J. PERRY 
Stonyhurst College Observatory, March 20 

ALL who are acquainted with the North of England are aware 
that the districts comprising the counties of Northumberland, 
Durham, and Yorkshire, are physically divided from that occu- 
pied by those of Cumberland, Westmoreland, and Lancashire 
by a ridge or watershed, formed by the Pennine chain, which is 
a range of hills averaging 1,700 feet in height, composed of 
Lower Carboniferous strata, through the centre of which runs 
the Pennine or ‘‘ Anticlinal Fault,” which has the effect of throw- 
ing the strata in a downwards direction to the east and to the 
west, like the slopes of the ridge of a roof of a house. : 
To the west of this ridge, in Lancashire, are low undulating 
plains of Coal measures, and Triassic rocks, much/faulted and 
covered with glacial drift, and in Cumberland and Westmoreland 
the high mountains and deep valleys of the Lake District inter- 
vene between it and the sea. These mountains, composed of 
Silurian rocks, existed as such, long before the anticlinal fault 
heaved the Pennine chain into existence, and long before the 
Oolite strata, forming the high Yorkshire Wolds on the 
eastern side of the watershed were deposited at the bottom 
of the sea. In the West Riding the moors have been cut, by the 
long-continued action of running water, into the deep ravines, 
or vales, which form so characteristic a feature of that district. 
It is an interesting question to observe how far this general 
arrangement of country, and the strata of which it is composed 
and the dislocations which the latter has suffered, appear to affect 
the direction, localities visited, and the distribution of the lines of 
greatest intensity, of the earth-wave which visited the northern 
counties on the night of the 17th inst. The tract over which it 
was felt, as far as at present known, would be comprised within 
a circle, with a centre about ten miles due east of Sedbergh, the 
diameter of which would be a line drawn from Dumfries to Don- 
caster, the farthest limits to the north-west and to the south-east, 
respectively, to which the earth-wave extended, The greatest 
effects appear to have been experienced in a belt, about thirty 
mules broad, running inside this circle, the inner margin running 
along the towns of Scarborough, New Malton, ¥ ork, Leeds, and 
Bradford, Preston, Longridge, Kendal, Penrith, Carlisle, New- 
castle, and Sunderland, and thence probably passing out to sea 


[March 23, 1871 

and curving round to Scarborough. The outer margin, or circle 
before mentioned, runs by the Humber, Doncaster, Manchester, 
Salford, Roby, I1uyton, Seaforth, Southport, and probably for 
some distance out to sea, Blackpool, west of Ulverstone and 
Coniston Lake, Dumfries, by the north of Tyneside, to the sea. 
If this belt be drawn on a map, it will be seen that that segment of 
the circle which occurs fom Sunderland to Scarborough, falls en- 
tirely out to sea, and up to the present time the earthquake is 
not known to have been felt on that coast between these points. 
It would therefore appear probable that this earth-wave traversed 
the country in a circular belt, the entire north-eastern segment 
and the outer margin of the Lancashire portion being beneath the 
sea; that the area of greatest intensity was near the inner 
margin, but especially at Preston, Lancaster, Ulverstone, and 
Blaydon, near Newcastle ; that the area in Yorkshire, within 
this belt, was not entirely free from the shock, as it was slightly 
felt in Wensleydale and Swaledale, on the eastern slopes of the 
Pennine chain, 
At Preston, where the earthquake occurred at 11.4 P.M. 
Greenwich time, the motion I observed to be from south-east to 
north-west ; the oscillation was considerable, and the hollow 
noise, which commenced and ceased with the vibration, resembled 
express trains running in underground tunnels, The air was 
close and oppressive, the wind S.W., the night starless and 
hazy, and the sky from the N.W. to the N.E. covered bya 
peculiar glare, resembling an incipient aurora, which lasted until 
1.30 A.M. 
In several places more than one shock is reported to have 
occurred ; thus at Singleton Brook, Manchester, the first shock 
occurred at 10.56; the second, lasting two seconds, at 11.5 ; 
and the third, lasting four seconds, half a second after. 
Two shocks near together were also felt’ at Leeds, the 
second being the sharpest, which was felt at Armley, 
Headingley, Woodhouse, New Leeds, Chapeltown, and 
West Bar. Two shocks also ocurred at Kendal, the first at 
6.20 P.M. ; the second, which was the most severe, at II.15, 
lasting twelve seconds, that experienced by myself at Preston 
lasting about seventeen. From Grasmere also three shocks 
are reported, the first being at 6.40, and the second and worst at 
11 p.M. At Ambleside, the first shock wasalso felt at 6.30, 
the true time probably of the two noted above, the second being 
atgiI.3 P.M. At Coniston, a slight shock was felt at 7.0 P.M. 
on the 17th, and another at 6.3 A.M. on the 18th. 
At Hexham, the chief shock is recorded as taking place at 
11.15 ; Ambleside, 11.3 ; Ulverston, 11.5 ; Preston (by myself), 
11.5; Bowdon, Manchester, 11.4 ; Singleton Brook, Manchester, 
11.4; Newcastle, 11.30; Leeds, 11.15; Penrith, 11.4; Liver- 
pool, 11.15; Kendal, 11.15; from which it will be seen that 
localities, comparatively near together, often differ more as to 
the time of occurrence than some of those far apart, and thus 
there is, therefore, strong reason to believe that these various 
observations (from 10.30 P.M. to 11.30 P.M.) represent one shock, 
occurring practically at thesame moment over the whole areaabout 
11.5 P.M. 
In the year 1786, on August 11, an earthquake which extended 
over nearly a similar area to the present, like it, slightly dis- 
placed the waters of Windermere and the Lake District was 
felt ; and the same district was also visited by an earthquake on 
Feb. 22, 1867, which was particularly felt on the north shores 
of Morecambe Bay. It is curious to observe that the zorthern 
margin of the area of the earthquake, which was felt over the 
greater part of central and southern England, in 1863, exactly 
coincides with the southern margin of the present, and that the 
latter, in its course to the north-west, directly crossed the 
Pennine chain in two places. 
H.M. Geological Survey, 
28, Jermyn Street 
C. E. de RANCE 
On Friday night last, March 17, at 11 P.M., we had a slight 
shock of an earthquake. I was reading, when suddenly I 
imagined I heard a carriage and pair drive rapidly up to the 
house, then rapidly drive on, there being a pause of half a second 
at least between the two rumbling sounds. After the second 
sound had continued a second, the house began to shake to such 
a degree that I rushed out of doors. The only damage done 
was that all the ceilings on the ground floor show cracks in the 
plaster. No doubt you will hear more of this from other corre- 
spondents. Gro, H. SAVAGE 
Nent Ilead, Alston Moor, Cumberland 
ee 
