A parapet is a barrier, an extension of the wall at the edge of a roof, balcony, walkway or other structure. The word comes from the Italian parapetto; the German equivalent Brüstung has the same meaning. Where extending above a roof, a parapet may be the portion of an exterior wall that continues above the edge line of the roof surface, or may be a continuation of a vertical feature beneath the roof such as a fire wall or party wall. Parapets were used to defend buildings from military attack, but today they are used as guard rails and to prevent the spread of fires. In the Bible the Hebrews are obligated to build a parapet on the roof of their houses to prevent people falling. Parapets may be plain, perforated or panelled, which are not mutually exclusive terms. Plain parapets are upward extensions of the wall, sometimes with a coping at the top and corbel below. Embattled parapets may be panelled, but are pierced, if not purely as stylistic device, for the discharge of defensive projectiles.

Perforated parapets are pierced in various designs such as trefoils, or quatrefoils. Panelled parapets are ornamented by a series of panels, either oblong or square, more or less enriched, but not perforated; these are common in the Perpendicular periods. The teachings of Moses prescribed parapets on roof edges for newly constructed houses as a safety measure; the Mirror Wall at Sigiriya, Sri Lanka built between 477 and 495 AD is one of the few surviving protective parapet walls from antiquity. Built onto the side of Sigiriya Rock it ran for a distance of 250 meters and provided protection from inclement weather. Only about one hundred meters of this wall exists today, but brick debris and grooves on the rock face along the western side of the rock show where the rest of this wall once stood. Parapets surrounding roofs are common in London; this dates from the Building Act of 1707 which banned projecting wooden eaves in the cities of Westminster and London as a fire risk. Instead an 18-inch brick parapet was required, with the roof set behind.

This was continued in many Georgian houses, as it gave the appearance of a flat roof which accorded with the desire for classical proportions. Many firewalls are required to have a portion of the wall extending above the roof; the parapet is required to be as fire resistant as the lower wall, extend a distance prescribed by building code. Parapets on bridges and other highway structures prevent users from falling off where there is a drop, they may be meant to restrict views, to prevent rubbish passing below, to act as noise barriers. Bridge parapets may be made from any material, but structural steel, aluminium and reinforced concrete are common, they may be of framed construction. In European standards, parapets are defined as a sub-category of "vehicle restraint systems" or "pedestrian restraint systems". In terms of fortification, a parapet is a wall of stone, wood or earth on the outer edge of a defensive wall or trench, which shelters the defenders. In medieval castles, they were crenellated.

In artillery forts, parapets tend to be higher and thicker. They could be provided with embrasures for the fort's guns to fire through, a banquette or fire-step so that defending infantry could shoot over the top; the top of the parapet slopes towards the enemy to enable the defenders to shoot downwards. In śilpaśāstra, the ancient Indian science of sculpture, a parapet is known as hāra, it is optionally added while constructing a temple. The hāra can be decorated according to the Kāmikāgama. Attic style Breastwork Merlon Redoubt Senani Ponnamperuma; the Story of Sigiriya, Panique Pty Ltd, 2013 pp 124–127, 179. ISBN 978-0987345141. Victorian Forts glossary Parapet What is a Parapet

Robert McKeen was a New Zealand politician of the Labour Party. He was Speaker of the House of Representatives, he received his education in West Calder, West Lothian, Scotland. In Scotland, he was active in the labour movement, worked as a grocer's assistant in a co-operative store, he emigrated to New Zealand in 1909, worked in coal mines on the West Coast before moving to Wellington, a grocery store. He was a union official. In the 1919 election, McKeen organised the campaign of the Labour Party in Wellington, he first was successful. He was the Member of Parliament for Wellington South from 1922 to 1946 Island Bay from 1946 to 1954, when he retired. McKeen was Labour's junior whip in 1935 and 1936, its senior whip in 1937 and 1938, he was Chairman of Committees from 1939 to 1946. Subsequent to that, he was the twelfth Speaker of the House of Representatives, from 1947 to 1950, he was on the Wellington City Council for 18 years, the Wellington Harbour Board for nine years. Bob Semple and McKeen were the only Labour city councillors during 1927–1929, they were parliamentary colleagues.

They were close friends, retired from parliament at the same time. McKeen stood for the Wellington mayoralty and the Council in 1941, but was defeated by the incumbent Thomas Hislop in a swing against Labour, he lost his seat on the council, although he was the highest polling candidate not elected, in 1938 he had been the second highest-polling candidate elected. He was Mayor of Otaki for six years in the 1950s. In 1935, McKeen was awarded the King George V Silver Jubilee Medal, he was appointed a Companion of the Order of St Michael and St George in the 1960 Queen's Birthday Honours, for services in public affairs as a trade unionist, Member of Parliament and Speaker of the House of Representatives. He married the daughter of Robert Russell, he died in Otaki on 5 August 1974, was buried at the Kelvin Grove Cemetery in Palmerston North. Hickey, Carina. From Coal Pit to Leather Pit: Life Stories of Robert Semple. Massey University. Retrieved 17 March 2015. Wilson, James Oakley. New Zealand Parliamentary Record, 1840–1984.

Wellington: V. R. Ward, Govt. Printer. OCLC 154283103. Who’s Who in New Zealand. Yska, Redmer. Wellington: Biography of a city. Auckland: Reed. ISBN 0-7900-1117-4

The Glynrhonwy quarries were two adjacent quarries in the Glynrhonwy area, north west of Llanberis, Wales. They were: Upper Glynrhonwy quarry, known locally as "Glyn Ganol" or "Middle Glyn", which operated from 1861 to 1930, Lower Glynrhonwy quarry, known locally as "Captain Taylor's Quarry", which operated from the early 1700s to 25 January 1930; the quarries operated internal railways of 2 feet gauge and were served by Glynrhonwy Siding off the LNWR's Caernarfon to Llanberis branch. Lower Glynrhonwy was acquired by the Air Ministry in 1939 for munitions storage, it occupied the site until 1961. During the Second World War the site generated two extra trains per day on some occasions; the railway siding was taken out of use on 18 December 1956. A 100 MW pumped storage project, marketed as a "quarry battery", received approval in 2017 and as at 2019 had reached the "detailed engineering design" stage. Boyd, James I. C.. Narrow Gauge Railways in North Caernarvonshire, Volume 1: The West. Headington: The Oakwood Press.

ISBN 978-0-85361-273-5. OCLC 650247345. Dunn, J. M.. Cooke, B. W. C.. "The Afonwen Line-2". The Railway Magazine. London: Tothill Press Limited. 104. ISSN 0033-8923. Mitchell, Vic. Bangor to Portmadoc: Including Three Llanberis Lines. Country Railway Routes. Midhurst: Middleton Press. ISBN 978-1-906008-72-7. Modern usage Snowdonia Pumped Hydro Modern usage The Engineer Wartime usage History Points