Murrell R ROBINSON: Project Architect
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The Lighthouse was completed in 1862 on Minto's Hill on an elevated site which had been used by the early inhabitants of Robben Island as a place to light fires at night to warn approaching ships of danger. The site is indeed the most elevated position on Robben Island.
A fine original working drawing - traced in black ink on linen with a subtle water-colour infill applied to the rear of the drawing - is held in the Roeland Street Archives in Cape Town. The drawing, titled 'Robben Island Lighthouse' was signed by J. Scott Tucker, Colonial Engineer, Cape Town, dated 21 April 1859 and describes a tapered octagonal Lighthouse tower with seven floor levels. The working drawing includes seven octagonal Floor Plans, as well as an Elevation and a Section.
Of particular interest is that the design of the Lighthouse was intended to protect and elevate the warning light as well as provide a residence to accommodate the lighthouse keeper. Ground floor was identified as the Kitchen, First Floor was set aside for the Living Room, Second Floor as the Sleeping Room and the Third Floor as a Store Room. The Fourth Floor - with domed masonry ceiling - was set aside as a Store Room. A double volumed space accommodated the light at the top most level.
Notwithstanding the octagonal plan described on the working drawing, the lighthouse tower was actually built with a circular plan. A circular painted concrete apron surrounds the lighthouse. A roughly made arrow - pointing due north - is inscribed into the concrete apron. Red painted concrete paths radiate from the apron, marking the original positions of paths through the surrounding garden.
A modern circular paved area now surrounds the concrete apron and is formed with concrete cobble-stones. A row of 9,2-inch Artillery Gun shells were placed in vertical position at equal centres, forming a perimeter row around the second paved apron. Each shell originally had a circular ring (now mostly lost due to rust) welded to the pointed tip to accommodate a rope.
The full height of the lighthouse tower can readily be likened to a classical column and divided into three component parts, i.e. the base, the shaft and the capital.
The circular base of the lighthouse tower was constructed as a cylindrical plastered masonry structure and has an external measured circumference of 21 250 mm (equivalent to 70-foot with an associated diameter of approximately 22-foot). The base comprises of a smooth plastered shaft with a substantial wall thickness and a large external champher at approximately door-head height, marking the transition between the base and the tapered shaft above.
The entrance door is deeply recessed from the external east face of the circular base and consists of a double, inward-opening teak framed and panelled door. Each door leaf has two fielded panels and the door is surmounted with a row of seven oval fixed fanlights - with the glass now removed and replaced with solid timber panels. The door and fanlight is accommodated within a hardwood timber frame. A broad granite step forms the threshold to the door.
The tapered shaft of the lighthouse tower was constructed as an un-plastered masonry structure using hammer dressed local stone with flush jointing and ruled horizontal and vertical pointing with a painted finish - possibly not original. A total of 28 horizontal courses are clearly identifiable and are capped with three carefully dressed granite courses - the upper one now painted - which combine to form a simple, elegant coved projecting cornice to the underside of the Main Gallery floor.
Windows are let into the shaft of the tower and are framed externally with a raised and quoined plaster surround with a keystone. The windows are deeply recessed from the external face of wall. Sloping external plastered window cills form an integral part of the window surrounds. The windows are all either placed on the axis of the front door or on the cross-axis and the cill heights relate to the various floor levels within. A black painted 'navigation' line is painted on the east face of the tower and it is presumed that this was originally a navigation aide to boats approaching the Faure Pier.
The timber framed sliding sash windows have unusual 'Georgian' style glazing bars with a fine inner triangular or V moulding, with glass set in putty in the external rebates. A total of eight windows occur in the shaft below the Main Gallery level, six of them 6 over 6 pane sliding sashes, with two of them 3 over 6 pane sliding sash windows directly below the Main Gallery level. A single 3 over 6 pane sliding sash window provided natural light into the Ground floor, opposite the entrance door.
The capital consists of the Lantern Room, accommodating the lamp and the complex lens with the Service Room directly below. The external Main Gallery with ogee profile metal balusters forming a balustrade - with ball finials fixed at intervals to the top face of the handrail - provided an external circulation space around the Service Room. An additional narrow raised Lantern Gallery provided safe access for cleaning the external faces of the Lantern Room glass.
The glazed windows of the Lantern Room are an interesting arrangement of 16 tapered steel framed windows. Each tapered window is sub-divided in its height into three panes with two horizontal v-section glazing bars. Every tapered window was inverted relative to its neighbour - creating an alternating facetted glazed curtain wall on a circular plan. The upper panes of two tapered windows - each on opposite sides of the lantern - were provided with a window opening. Robust rectangular metal brackets were fixed externally to the steel mullions as points of attachment for window cleaners.
The walls of the Service Room comprise of 16 rectangular flat cast-iron panels bolted together, following the same alternating 'beat' established by the Lantern glazing above it. On two opposing sides of the Service Room a 'full' panel of the cast iron wall in each case accommodated a narrow door providing access onto the Main Gallery.
The tower is capped with a domed sheet metal roof with an ogee profile and a setting-out geometry based on a 12-sided polygon (dodecagon). The metal dome was prefabricated using 12 tapered sections of rolled light gauge metal sheeting, each of the tapered roof sections with the same 30 degree vertex angle, an ogee profile and a bottom edge with a standard length of 1/12 of the outer perimeter. The edges of the tapered sheet metal sections of the dome were overlapping and riveted together to form seams.
The upper terminal of the ogee dome is surmounted with a spherical sheet metal finial which in turn supports a simple rotating weather vane. A curved ladder formed of two flat bars with round bar rungs provides access to the finial for inspection and maintenance purposes. A circular ring of round bar around the finial and mounted just above the surface of the dome provides an attachment point for a rope.
The eaves line of the ogee dome was formed with a narrow cast iron ogee profile gutter. Two narrow diameter downpipes on opposite sides of the dome discharge down to the floor of the Main Gallery. Of particular interest is that the external eaves edge gutter is not divided into 12 full segments, matching the 12 equal faces of the dome - but rather into 8 full segments and 8 half segments, the full segments alternating with the half segments. This particular layout appears to be a direct consequence of the 16 sided geometry of the glazed wall of the Lantern Room directly below.
The main electrical supply cable from the adjacent free-standing Engine Room passes through the lintel above of the Ground floor window on the west side. A lightning conductor is fixed to the external face of the wall on south side.
Access between the different floor levels was achieved with individual narrow timber framed staircases, the inner stringer and the inner edge of the treads following the inner face of the circular lighthouse wall. Each curved flight rises clockwise between the different floors in flights of thirteen risers - some of the flights terminated at the upper floor with a narrow door - now removed.
A small scale spiral staircase with timber treads, decorative cast-iron winder ends and timber handrail and balustrade provides access from the Fourth floor up to the Service Room. Another small scale spiral stair - this time of prefabricated cast iron components - provides access from the Service Room floor up to the Lantern. This spiral stair terminates on a narrow gallery of perforated cast iron floor panels which surrounds the lantern.
The actual light comprises of a large complex domed assembly of polished glass prisms mounted in a supporting framework constructed of solid brass, in turn supported on a heavy cast iron central shaft within the Service Room. The original light source mounted within the lantern has recently been replaced with a modern LED fitting.
Statement of Significance
A fine example of a late Victorian light house structure in original intact condition. A well proportioned landmark on Robben Island. Forms an important layer in the history of Robben Island and in particular maritime history. Significant marker in the provision of warning lights to shipping into and out of Table Bay.
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