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the sheltered situation of Blind Bay are safe in almost any kind of 
weather. During northwesterly gales the neighbouring Croixelles 
Harbour offers a perfectly safe place of refuge. The boulder-bank 
is one of the natural curiosities of Nelson. It consists of rounded 
pebbles on boulders. In time of high-water a large portion of it 
is under water; at low-water it is dry throughout its whole length. 
The largest and heaviest boulders are towards the sea side; on the 
harbour side the boulders grow smaller; and at a point close by 
the entrance to the harbour they are so small, that vessels there 
can drive on the strand without any damage , thus using the place 
as a natural dry-dock in consequence of the great difference of the 
water level between ebb and flow . 1 The boulders consist nearly 
all of one and the same kind of a syenite, containing blackisli- 
green hornblende, flesh-coloured feldspar and a small quantity of 
iron-pyrites. On following the narrow bank from South to North, 
it is easily observed, that the boulders towards North grow larger 
and more angular, and originate from a precipitous bluff of syenite, 
called “Mackay’s knob” which 
abuts upon the sea a little be- 
yond Drumduan, the residence 
of Mr. Mackay. The frag- 
ments constantly falling from 
the cliffs are gradually rolled 
towards South by the heavy 
northerly swell combined with 
a strong current of the sea, 
passing in time of springtide 
with considerable velocity along 
the coast . 2 The reason of their 
1 The springtide in Nelson Harbour rises 14 feet. 
2 In a similar manner the remarkable sand-bar, Cape Farewell Spit, extending 
from Cape Farewell 22 miles into the sea, owes its origin to the currents of the sea 
running on the one side along the West coast, on the other along the shores of 
Golden Bay. The direction of the sand-bar is the resultant of the direction of those 
currents and of the moving force of the westerly and north-westerly winds prevail- 
ing on the West coast. 
The boulder-bank, Nelson Harbour. 
