This is the first sundial made for the Irish Lighthouse Service in 1833.  It was one of a batch of 24 sundials which cost £2 each. The lighthouse clocks were made by Charles Sharp of Dublin and cost £7.17.6 each What time are Lighthouses lit?

In the early 19^th century the answer depended on who you asked. Up until this time Irish Lighthouse Keepers were required to estimate the time at dusk and dawn when they should light and extinguish their lanterns. The issue was brought to the fore in the Board Minutes of 1832 with a letter from the Commander of the Royal Mail paddle steamer ‘Crocodile, who complained to the Irish Lighthouse Authority that his vessel was put in danger while entering Waterford Harbour due to the light at Hook Tower not being exhibited until well after dusk.  He requested that the lighting-up and extinguishing times at Irish Lighthouses be regulated, as was the case in Trinity House.

The difference in timings arose with Trinity House instructing Lighthouses ‘to Light up every evening at Sunset’ while under the Ballast Office in Dublin the Light Keepers were ordered ‘to Light when it is dark, thus leaving it to the care and accuracy of each individual Lightkeeper to determine the difficult question, when twilight ends and when darkness commences’.
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The Board ordered George Halpin, Inspector of Lighthouses, to carry out a full investigation. Halpin clarified that Lightkeepers in Ireland were ordered to Light ‘at the going away of daylight in the evening when the adjacent land or coast becomes in the least indistinct, not when it is dark…’ He states that he has never received a complaint from other Commanders of Steam Packets and concludes that ‘it would be injudicious and perfectly unnecessary to alter the time now observed for Lighting’. This resistance to change may also have been due to the cost of sperm oil, which was used at the time to fuel the lamps.  

Dissatisfied with this response, further petitions followed from the Lord Lieutenant of Ireland, the Post Master General and the Admiralty. This pressure resulted in the Board ordering ‘that the regulations of the Trinity Board as to Lighting the Light Houses will be adopted’ and agreed to supply each of its 24 major Lighthouses with a clock and sundial with which to ensure its constant accuracy. The first of the new dials was duly installed at Hook Point in 1833 and is still retained at that station.