Descriptive Report.
95
Barking.—Slight shock felt by one or two persons.
Basildon, 4 miles S.E. of Billericay.—Slight shock felt.
Bergholt (East and West).—Shock distinct; slight damage.
Billericay.—Shock slight.
Black Notley.—Shock felt rather strongly in some houses.
Bocking.—Mr. E. B. Knobel, Sec. E.A.S., who resides at
this place, has been good enough to forward me the following
report, which, as coming from a well-known scientific ob-
server, I here give in extenso :—
"I was standing on the first-floor of a building when the
shock came—immediately watched the wall at the side of the
window, and saw by reference to the clouds that it swayed
considerably out of the perpendicular. Felt certain at once
it was an earthquake shock, and took time by my watch,
which had a known error, and which was confirmed by an
observation of the sun the following day as 9h. 18m. G.M.T.
Duration of the shock estimated as under three seconds.
I collected the following facts within an hour of the
occurrence:—
1. The shock caused a burst of steam to escape out of the
safety-valve of a large steam boiler in the factory in which I
was at the time. There was about 20 lbs. pressure of steam
in the boiler at the time, and the safety-valve was weighted
to 30 lbs. The boiler was evidently jerked up and fell
quicker than the valve could follow, and consequently steam
blew off for an instant.
2. A dye bark, 12 feet long and 2 feet 4 inches wide, filled
with water, occupied the following position. Bearings being
true, not magnetic :—
Fig. 12.—A, position of observer. The arrows show the direction
of the waves.
At the moment of the shock, a man was standing at a,
with his hands on the side of the bark. At the commence-
ment of the shock he was tilted forward towards the S.E.,
and he felt the bark go with him, then he swayed back. A
wave was produced in the water which started from the
N.W. side of the bark, and this moved back and forth from