OF THE 20TH OF NOVEMBER, 1887. 
57 
there may have been in addition a sound arising from the rapid 
motion of the meteorite through the air ; of this latter phenomenon 
there is little or no evidence, and I am more inclined to refer all 
the effects observed to a series of explosions, whether of the main 
mass of the meteorite itself, or of liquefied air carried in advance 
of the moving solid body, it is impossible to say. Such a series 
of explosions, whose shock would be transmitted eastward in 
successive sound-waves rapidly following one another, would 
clearly account for the sounds recognised to the eastward; while 
in the area more immediately adjacent to the locality of explosion, 
several explosions might perhaps be so nearly identical in time as 
to reach an observer as a single sound-shock, or the concussion set 
up at the point nearest the observer might be so much more powerful 
as to render other sounds for the moment indistinguishable. We 
are in some general difficulty in accounting for the variable loud¬ 
ness of the shock experienced in different, but adjacent localities ; 
and especially is it difficult to give satisfactory grounds for the 
violence of the shock noticed in certain isolated districts at some 
distance from the assumed track and localities of explosions; for 
instance we have a group of places near Welwyn, in Hertfordshire, 
from which I have reports showing a considerable aerial disturbance. 
And yet this district is at least 12 miles from the assumed track of 
the meteorite, and is isolated, in a measure, from other localities in 
which similar effects are recorded. Probably the configuration of 
the ground here and elsewhere has affected the question ; and with 
regard to this point I may mention one instance which may serve 
as an illustration of what may be, possibly, more or less worth con¬ 
sideration. I refer to the reports from Mr. Iredale, of Digswell 
Mill A 1 Welwyn Yiaduct is a high, brick structure, running due 
1ST. and S., and carrying the Great Northern Railway across the 
valley of the Mimram. The mill and garden referred to in Mr. 
Iredale’s letters lie on the E. side of, and almost under, this viaduct. 
It is probable that a sound-wave coming from the W. would be to 
some extent pent in by the sides of the valley, and upon reaching 
the transverse partial barrier of the viaduct might be caught and 
echoed in its arches in the manner described. The very distant 
and isolated extension of the sound to Cubbington, near Leamington, 
so far to the N. or N.W. of the assumed localities of explosions, 
is curious. 
The effect of the shock upon animals, both wild and domesticated, 
should be noted. In a number of cases pheasants are reported to 
have crowed, or to have given other signs of uneasiness. It appears 
that at Westley the crowing of pheasants was noticed at the time 
of the Erith gunpowder-explosion; but Mr. Mathison’s Aynhoe 
correspondent remarks that pheasants generally call out when it 
thunders, and this is true also of dogs. 
In considering the sound-effects in the western section, subject 
as such a matter must be to many qualifications, the fair conclusion 
seems to be that we have on the course of the meteorite three 
* P. 46, ante. 
