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Establishment of the Dent Island Lightstation

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3.3. Establishment of the Dent Island Lightstation

Commander Heath, the Portmaster, wrote to the Colonial Treasurer in February 1878 to request that … the Colonial Architect may be instructed to prepare plans & specifications and call for tenders for a Lighthouse at Cape Cleveland & on Dent Island Whitsunday Passage. The towers to be the same size as that at Flat Top Island but with a trunkway in the centre for the clockwork weights to travel up & down as at Lady Elliots’ Island. With each of the Light houses two cottages will be required for the keepers. (WOR/A268 In-letter 4484 of 1890, quoted in Thorburn 1967).
The Treasurer passed the request on to F D G Stanley, the Colonial Architect. Stanley reported in April that the documents were almost ready, and in May called for tenders for the erection of both lighthouses. Three tenders were received for each lighthouse. William Peter Clark submitted the lowest tenders — £1820 for Dent Island and £1670 for Cape Cleveland — and his tenders were accepted.
In December 1878 Stanley reported on a visit to Dent Island: Having arranged for detention of the “Victoria” S.S. [steam ship] for two hours in passing through Whitsunday Passage — I landed with the Contractor and with considerable difficulty reached the top of this island and found a suitable spot for the Lighthouse, commanding the Channel both to North and South, also a level site for Cottages. The work is now in progress, the buildings being framed up in Brisbane (QSA WOR/A158 In-letter 6178 of 1878, quoted in Thorburn 1967).
original plan of the design of the dent island lighthouse and cape cleveland lighthouse dated 1878

Figure — Contract drawing for the lighthouse, 1878

Light houses: Dent Island & Cape Cleveland, a contract drawing prepared in the office of the Colonial Architect. The contractor William Clark signed the drawing in the bottom right corner, but part of his signature has been lost. (Source: National Archives of Australia, series J2775, item 1717459).
It appears that William Clark got into financial difficulties around this time. He transferred his contracts to others to complete (to John Clark for the Dent Island project and to James Wiseman for Cape Cleveland); James Campbell, supplier of building materials in Brisbane, sued William Clark for payment of debts; the Crown Solicitor and various other lawyers got involved; William Clark was insolvent for a time.
Despite these distractions the building work was finished, and the lighting equipment installed and commissioned. The lighthouse was first lit at the end of October 1879 (Heath 1879). A contemporary newspaper article describing a journey through the Whitsunday Passage mentioned that …a young woman and her baby had to be landed at Dent Island, where a new lighthouse has lately been built, of which her husband is the keeper (Anonymous 1879).
There were two separate cottages at the lightstation; one was for the principal lightkeeper with his family; and the other for the assistant lightkeeper and his family. No drawings of these cottages are known to survive, but they were probably similar to those for Cape Cleveland shown in Figure . A photograph published in 1915 shows that they were similar to those built at some other Queensland lightstations (Figure ).1
The keepers took turns keeping watch through the night in the tower, where their principal duty was to tend the kerosene wick burner and to wind up the weight that drove a clockwork to rotate the lenses. Dent Island Lighthouse was originally fitted with a fourth order revolving dioptric light. This is an assembly of Fresnel lenses and refracting prisms with a focal radius of 250 mm that rotated on a vertical axis around the kerosene lamp, projecting several narrow beams of light out towards the horizon. Because of the regular rotation of the lenses, ships’ officers saw distinct flashes of light as each beam passed over their ship. Each lighthouse had its own character or pattern of flashes which was shown on navigation charts, and which allowed the ships’ crew to recognise which lighthouse it was.
The keepers’ daytime duties included maintaining all the equipment and facilities of the station, monitoring vessels traversing the passage, signalling to and from the vessels, and dealing with quantities of kerosene (brought by the government steamer) and household supplies (brought by contractors). To support these functions, the station was equipped with a workshop, a flagpole, and a boat shed.
original drawing of the keepers\' cottages at cape cleveland. note that no corresponding plan for dent island has been located but it is likely the cape cleveland cottages were similar to the dent island cottages.

Figure — Keepers' cottages at Cape Cleveland

Lightkeepers Cottage and Assistant Lightkeepers Cottage for Cape Cleveland, a contract drawing prepared in the office of the Colonial Architect, and signed by the contractor William Clark. No corresponding drawing of the original Dent Island cottages is known to survive, but it is likely that they were similar to these. (Source: National Archives of Australia, series J2775, item 1717460).

3.3.1 The lighthouse

As was typical for this series of lighthouses, the Dent Island tower was round in plan and tapered in profile, forming a truncated cone. The outer walls were framed with sawn hardwood posts and rails, bolted together with joints reinforced with wrought iron straps and brackets. The walls were lightly braced by timber braces, which would have served to stabilise the timber structure before the iron shell was fitted. At Dent Island there was just one intermediate floor with hardwood joists and pine floorboards. In the centre of the tower was a vertical timber weight tube, which formed a central support for a winding timber stair that ran part of the way up the tower. On the upper level, where the conical tower was too small to fit a stair, there was a fixed ladder up to the level of the light room and balcony.
The tower frame was supported at the bottom by a segmented cast iron ring that formed a base, bolted to a massive concrete footing and floor cast within a low stone wall. The timber posts were bolted to lugs made as part of the iron base ring. At Dent Island, because the tower was quite short, a pit was formed in the middle of the floor to provide a longer drop for the weights that powered the clockwork that rotated the lens.
The tower was clad with a covering of wrought iron plates, about 3 mm thick, which were rolled to conform to the conical shape. The plates were lapped and riveted, and screwed to the timber framework and to the iron ring at the base. A timber door was fitted at the bottom of the tower, and glazed windows at each floor level.
At the top of the tower was a timber-framed structure, which formed the floor of the lantern room, and the projecting balcony that surrounded the lantern room. This balcony had a flooring of timber boards with a waterproof covering of lead sheet.

The lantern (the structure which enclosed the lantern room, and which protected the optical apparatus) had three main parts — the base, the glazed section and the roof. The base (sometimes called the murette) was round in plan, framed in timber, clad with iron on the outside and with timber boarding inside, and capped with an iron sill. There was a low door in the base through which the keeper could crawl out onto the balcony. Above the base was the glazed section, with flat trapezoidal glass panes in a slender framework of iron. On top was the lantern roof (sometimes called a dome or cupola) of galvanised iron sheeting on an iron frame, curved to form a hemispherical dome. At the peak of the roof was a weatherproof vent for the lamp smoke to escape. All of these parts were locally designed and made in Queensland.

The optical apparatus was mounted inside the lantern room, and was manufactured by Chance Brothers & Company, lighthouse engineers, in their factory at Smethwick near Birmingham, United Kingdom. The apparatus consisted of the rotating assembly of lenses and prisms, the kerosene lamp at its centre with a number of circular concentric wicks, and the clockwork to rotate the lens assembly.

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