On 10 May 2016 we visited the first of the hoped for 45
lighthouses. Having overnighted at Paternoster, we were only 5 km from the Cape
Columbine lighthouse. The LH is in the CC Nature Reserve, where a small
entrance fee is payable. The structure is square in cross section with fluted
corners.
A foggy morning meant a late
start to the day. We were welcomed by Wayne Brown (pictured in conversation
with me), having phoned (022 752 2705) beforehand to advise of our
intended visit.
He explained the operation
of the LH, both historical and current. Various light sources had been used
over the years, but currently a 400 watt metal halide lamp is in operation. The
earlier fog signalling system was a pair of foghorns (diaphones) operated by 100
psi compressed air. I guess this was effectively a wind instrument, like a
bugle, but not as musical. The compressor, 3 large air reservoirs and the final
air tank (pictured below) have been preserved. The one diaphone (darker grey)
is visible behind me in the picture. It protrudes through the wall.
Wayne escorted us through the
lower buildings and tower. The visitors’ book on the first floor of the tower
was duly signed. The lantern house was fascinating. The lens system is much
larger and more complex than expected and the lamp appears to be very small. The
rotational gearing system is driven by a surprisingly small electric motor. A large pipe (about 300mm in diameter) extends vertically all the way up
the tower but is now redundant. Its purpose was to house cables and weights
which had to be hoisted manually every 3 hours to drive the rotating mechanism.
The tour ended with a question and answer session which
elicited some interesting information. The pedestal (lens and its supports)
floats in a bath of mercury, hence very low friction and the small motor. The
lens system directs the light by both reflection and refraction. Wayne used the
term catadioptric for this.
Wayne explained that the fog
signalling system had been re-sited when the technology changed from compressed
air to an electrical nautophone.
As there was still some fog
at sea, the fog detector (at the top of the above structure) was still in
positive mode. We certainly experienced the sound at close hand, in fact for
2.5 seconds at one minute intervals.
Drafted 23 May
2016
