Document ID: chunk:federal_register_of_legislation:F2022L01056:clause:7b_2027:p3
Version: federal_register_of_legislation:F2022L01056
Segment Type: clause
Provision Reference: sch 7B cl 2027 (pt 3/8)
Character Range: 157402–160186

of metal which retain the panes of glass in a window. Often consist of vertical angled steel members joining between done support ring and murette. Often the glazing bar has a tenon that matches a mortise in the murette. Astragals are arranged helically. Helical and trapezoidal glazing bars were used where a fixed light was in use (flashing or non-rotating) as vertical bars cut off portions of the light. In comparison, a helical bar design crosses the light source at an angle, obscuring part of it.
I
Incandescent kerosene
A light fuel once utilised by lighthouses to ignite and fuel the lantern. Cape Leeuwin used kerosene to fuel its lantern before its introduction to electricity.
Intermediate floors Levels found mid-way up a building. Cape Leeuwin's intermediate floors are constructed of iron checker plate.
Internal catwalk An open landing inside the tower complete with handrail.
L
Lantern The glazed enclosure at the top of a lighthouse, which surrounds and protects the optical apparatus. It contains the optical apparatus, made up of the lantern roof, lantern glazing and murette sections.
Lantern floor The level in a lighthouse at which the lantern is installed, and by which access may be gained to the optical system and to the inside and outside of the lantern glazing. The lantern floor is generally at or near the same level as the catwalk and can be made from steel, concrete, or timber.
Lantern glazing The middle section of the lantern, circular or polygonal in plan, between the lantern roof above and the lantern base below, made up of glass panes held in a framework of glazing bars. On the landward side there may be blank panels in place of glass, or other opaque construction. Types of lantern glazing include: flat and curved trapezoidal panes and curved diamond/triangular panes. Cape Leeuwin uses curved rectangular panes.
Lantern roof Roof of the lantern. Usually made of copper sheeting over a framework of rafters.
Lens assembly A transparent optically refracting element of glass. The surface is usually spherical in form.
Light source Electric lamps and LEDs now illuminate most lighthouses.
Lighthouse The principal structure of a lightstation, generally made up of a lantern, balcony and tower.
Lightstation A precinct containing a lighthouse structure and other related buildings, for example. Keepers' cottages, store room and signal house.
M
Mercury float mechanism Mechanism whereby the base of a lighthouse's lens is submerged in a mercury-filled bath and is then rotated without friction.
O
Oil store A building or similar structure built for a specific purpose. Cape Leeuwin's oil store is located around the base of the tower.
Optical apparatus Equipment to provide, direct and control the light emitted by the light source. Comprised