In brief

In 1887 a Chance Brothers hyper-radial optic was installed at Tory Island. Reconstructed and split in the 1920s, it continued as two heritage objects: one at Tory Island and one that later became The Great Light in Belfast.

Journey Map

Geographic movement of the Mew/Belfast branch across mapped heritage places. Smethwick workshop and Dun Laoghaire restoration are documented in the timeline but have no published coordinates.

1. 1

   Tory Island LighthouseOrigin

   Irish Lights records a major optic alteration at Tory Island in 1887; the hyper-radial lens lineage identifies Tory Island in the same original-object chain.

2. 2

   Mew Island LighthouseBranch B

   Irish Lights records a biform optic transferred from Tory Island replacing Mew Island's original triform optic in 1928.

3. 3

   The Great Light, BelfastPreservation

   The Mew Island component is preserved and displayed as The Great Light at Titanic Quarter, Belfast.

Interactive Movement Timeline

1. 1887Origin1887 — Tory Island optic

   Irish Lights records a major optic alteration at Tory Island in 1887; the hyper-radial lens lineage identifies Tory Island in the same original-object chain.

   Evidence: 3 sourcesConfidence: medium

   Place: Tory Island LighthouseObjects: Tory Island Chance Brothers hyper-radial opticSources: Hyperradiant Fresnel lens - Tory Island entry, Irish Lights - Tory Island Lighthouse, Irish Lights - Tory Island Lighthouse
2. 1923-1928Reconstruction1923–1928 — Chance Brothers Smethwick Works

   The object lineage leaves Tory Island and is reconstructed by Chance Brothers in Smethwick before the Mew Island transfer.

   Evidence: 2 sourcesConfidence: medium

   Place: Chance Brothers Smethwick WorksObjects: Tory Island Chance Brothers hyper-radial opticSources: Irish Lights - Tory Island Lighthouse, Mew Island Lighthouse - hyperradiant optic
3. 1923-1928SplitOne optic becomes two components

   The reconstructed optic lineage branches into a Tory-retained component and a component later installed at Mew Island.

   Evidence: 3 sourcesConfidence: medium

   Objects: Tory Island Chance Brothers hyper-radial optic, Tory Island retained hyper-radial optic component, The Great Light / Mew Island hyper-radial optic componentSources: Hyperradiant Fresnel lens - Tory Island entry, Irish Lights - Mew Island Lighthouse, Hyperradiant Fresnel lens - Tory Island entry
4. 1923Branch ATory-retained component

   Irish Lights records the Tory Island vaporised paraffin era with a biform 1330mm dioptric annular lens.

   Evidence: 1 sourceConfidence: high

   Place: Tory Island LighthouseObjects: Tory Island retained hyper-radial optic componentSources: Irish Lights - Tory Island Lighthouse
5. 1928Branch BMew Island component

   Irish Lights records a biform optic transferred from Tory Island replacing Mew Island's original triform optic in 1928.

   Evidence: 1 sourceConfidence: high

   Place: Mew Island LighthouseObjects: The Great Light / Mew Island hyper-radial optic componentSources: Irish Lights - Mew Island Lighthouse
6. 2014PreservationRemoval and Irish Lights restoration

   The Mew Island optic component was removed and restored in Irish Lights workshop context before public display.

   Evidence: 1 sourceConfidence: medium

   Place: Irish Lights workshop, Dun LaoghaireObjects: The Great Light / Mew Island hyper-radial optic componentSources: Mew Island Lighthouse - hyperradiant optic, Mew Island Lighthouse - hyperradiant optic
7. 2015-presentPreservationThe Great Light, Belfast

   The Mew Island component is preserved and displayed as The Great Light at Titanic Quarter, Belfast.

   Evidence: 4 sourcesConfidence: medium

   Place: The Great Light, BelfastObjects: The Great Light / Mew Island hyper-radial optic componentSources: Mew Island Lighthouse - hyperradiant optic, The Great Light, The Great Light

Relationship Graph

This graph is not a map of places. It is a map of identity transformation. It shows how one original optic became multiple connected heritage objects through reconstruction, split, relocation, restoration, and public display.

Evidence

Official and object-specific sources carry the strongest confidence; secondary sources are shown as corroborating context.

Source Baseline

• Irish Lights: Tory Island Lighthouseofficial
• Irish Lights: Mew Island Lighthouseofficial
• The Great Lightobject-specific
• Great Lighthouses of Ireland: The Great Lighttrusted_curated_source
• Chance Heritage Trustheritage-organization
• Wikipedia: Mew Island Lighthousesecondary
• Wikipedia: Hyperradiant Fresnel lenssecondary

Identity Changes

• Original objectThe Tory Island hyper-radial optic is treated as the root identity for this journey, with later components linked by split_into and derived_from relationships.
• Reconstruction and splitThe reconstructed lineage is no longer a single heritage object: the Tory-retained component and the Mew Island component continue separate object lives.
• Public display identityThe Mew branch later becomes publicly known as The Great Light while remaining traceable to the Tory Island optic lineage.

Current Status

• Component A is modeled as the Tory Island retained hyper-radial optic component.
• Component B is modeled as the Mew Island component now displayed publicly as The Great Light in Belfast.
• The journey keeps official/object-specific sources above Wikipedia corroboration in confidence display.

Open Questions

Research still in progress — these do not affect accepted relationships above.

• Confirm exact workshop dates and documentary wording for the Chance Brothers reconstruction window.
• Add primary archival evidence for the precise 2014 restoration workflow and 2015 Belfast installation sequence.
• Resolve whether the Tory-retained component requires finer subcomponent modeling beyond the current component-level identity.