186 
with the sides of the channel. These were known familiarly 
to the workmen and the visitors as “boulders.” I succeeded 
in securing the largest isolated one, which is so well shown in 
the photograph, and it is now in our Botanic Garden at the 
College. A blast hole had already been bored in it, and it was 
about to be broken up, when I fortunately visited it. Its 
weight is about 25 cwts., and its dimensions are 4 ft. 6 in. 
in diameter and 1 ft. 9 in. in thickness; a section in hori- 
zontal plane would be nearly a circle. : 
The question naturally arises in the mind of the observer, 
what explanation can be given of these singular conditions ? 
Standing at the point from which the sketch is taken, and 
looking westward through the cutting, it required but little 
stretch of the imagination to fancy oneself in the bed of a 
stream which had hollowed out the channel through which 
the rails are now laid—the rocky sides of the stream weathered 
by wind and water into the fantastic rounded bosses of stone 
which furnish the features of this cutting. Or it might well 
be that an ancient shore once stretched eastward of the present 
outcrop, and that the channel is but one of many excavated by 
the tidal wash of an old Middle Oolite sea. 
One or two further observations relating to the sand which 
filled up the wide channel, as well as the interspaces between 
the projecting masses of rock may be useful in helping to a 
solution of the problem. 
When the channel was quite cleared out it was very notice- 
able that this sand was variously coloured in zones of red, 
brown, or deep yellow, which zones could be traced continuously 
through the whole length exposed. Between the projecting 
bosses, in deep recesses, these coloured bands ran uninterruptedly 
throughout. The sand is remarkably pure. No fossil remains, 
none of the wood which is so plentiful in the upper rock, were 
found init. It contains Chloride of Sodium and traces of Iron, 
but is otherwise almost absolutely pure sand. 
The heavy rains of last spring and summer speedily washed 
it down from the hollows of the rock, and left standing in still 
higher relief the prominent bosses seen in the photograph. 
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