150 The East Anglian Earthquake.
Greenwich.—The following has been received from Mr.
William Ellis, of the Royal Observatory:—
" I am requested by the Astronomer Royal to inform you
that our earth-current registers both indicate that small
movements of the respective needles occurred yesterday, April
22nd, at 9 h. 20 m. It happened that the circuits were
interrupted at the time for determination of the zero positions
of the needles. They were thus not under the influence of
any earth-current, which makes the indication very certain.
The earth-current needles are very light. There is nothing
to be seen in the registers of the heavy magnets. The earth-
quake shock was distinctly perceived by myself, whilst sitting
writing at my official desk. We are unable to give any
indication in regard to direction of movement of the shock."
In a later communication (April 26th), Mr. Ellis adds :—
"You would understand that the motion of the earth-
current galvanometers (slight vibration) at 9 h. 20 m. a.m.,
on April 22nd, mentioned in my letter of the 23rd, was not
produced by earth-current, but was simply caused by the
earthquake shock. Closer examination of the magnetic
registers, those of declination and horizontal force, shows
that those magnets were also put into very slight vibra-
tion."
At 28, Groom's Hill, Mr. T. V. Holmes, F.G.S., informs
me that his wife, who was in bed at the time, distinctly felt
the vibration of the bed, and was led to ask whether one of
the chimneys in the adjoining house was being swept at the
time (about 9.20). Direction apparently E.N.E. to W.S.W.
The house is on Thames Valley gravel, 45 feet above
Ordnance datum. Below the gravel is either chalk or Black-
heath and Woolwich beds, according to the side of the fault
that the house is situated upon; the position of the fault is
here unknown owing to the covering of gravel.
Writing from 9, Maze Hill, Mr. F. A. Saw states that the
undulating movement of the bed was felt both by his brother
and himself, who were in bed on the fourth storey. Motion
apparently E. to W. Time about 9.15 (?).
Herne Bay.—Crockery rattled and bells rung.