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Manora Lighthouse
Manora - Tallest Lighthouse of Pakistan 11008351 crop.jpg
Manora Lighthouse, the tallest lighthouse in Pakistan, as seen in December 2005
France3470/sandbox3 is located in Sindh
France3470/sandbox3
Location Manora,Karachi, Pakistan
Coordinates 24°47′38″N 66°58′39″E / 24.79389°N 66.97750°E / 24.79389; 66.97750Coordinates: 24°47′38″N 66°58′39″E / 24.79389°N 66.97750°E / 24.79389; 66.97750
Year first constructed 1851
Year first lit 1889 (current tower)
Tower shape Conical
Markings / pattern Red and white horizontal bands
Height Tower – 28 m (92 ft)
Focal height 45 m (148 ft)
Current lens hyperradiant Fresnel lens (1909)
Range 26 nmi (48 km; 30 mi)
Characteristic Fl. W 7.5s

The Manora Lighthouse is located at the port of Manora, Karachi in Pakistan, on the Arabian Sea, where it is the tallest lighthouse in the country at a height of 28 m (91 feet). Built first as a light station in 1851, then extensively rebuilt in 1889, it still remains operational today as an active navigational aid for ships. The lighthouse is considered the second oldest light station in the former British Indian Empire. It is a simple conical masonry tower, with a lantern and gallery, with the seaward side of the lighthouse painted with horizontal bands of red and white. As of 1909, the lighthouse features a hyperradiant Fresnel lens produced by the English company Chance Brothers. The management of the lighthouse is undertaken by the Karachi Port Trust and although the site is open to the public the island is itself a restricted zone due to it being surrounded by Pakistan Navy bases. There is no public access to the the tower.

Construction[edit]

light western harbour in 1848.[1] "The British constructed a lighthouse as part of their fortifications at Manora Point (24o47.3N 66o58.3E), which marked the western side of the entrance to the Bay leading to Karachi. The fixed light was visible for 16 miles (25.7 km) from its height of 120 feet (36.4 m)."

Karachi, the former capital of Pakistan, is the largest city and main commercial centre of the country and the capital of Sindh province as a port on the Arabian Sea north-west of the mouth of the Indus. Although its history of a port is little known prior to the 18th century, the port it is believed to be ancient. The British captured Manora in 1839 and made it their initial base of operations in what is now Pakistan. However, it remained modestly sized until the British conquest of Sindh in 1843 when the port developed as a vital centre to support cotton exports.[2] Manora, a bluff rocky headland, projecting in a south-eastward direction from the mainland, and leaving a space of about two miles between the extreme point and the coast to the east. In the harbour and within the entrance are some rocky islets, which are seen from the sea over the low isthmus connecting the point of Manora with the coast to the west.[3]

Although a light on the Manora Breakwater had been in existence for, increased traffic to the port meant that there was a need for a light station was establish at the port of Manora in 1851.[2] "The British constructed a lighthouse as part of their fortifications at Manora Point"[4] The lighthouse is located in the British historic district near the southeastern tip of the peninsula.[4]The lighthouse of 1851 was a 50 foot tower standing at an elevation of 119 feet above sea level. It was visible from 15 to 16 miles off and had a focal plane of 120 feet.[2][5] This tower was unpainted.[citation needed]

The area was known for having strong north-easterly winds between November and March with gales in January from the west-southwest and very irregular tides. During the Southwest monsoon, it was advised that vessels avoid the point entirely and instead head 18 ½ miles north to Cape Mouse, Ras Muari. If the weather was particularly bad ships were not to attempt an approach at Karachi Bay.[2] According to Ken Trethewey, this is one of the oldest light stations in the former British Indian Empire.[4] The building next to the lighthouse is St. Paul's Church which was built in 1964.

Manora is the Brighton of Karachi—or rather will be—where the inhabitants resort for change of air; it is well adapted for bathing, and is cool and pleasant from its vicinity to the sea...Point Manora is a high bluff, on which is the lighthouse, with a good fixed light, visible 16 to 18 miles off; but the whole point is rapidly wasting away, and will in time be only a sandy spit.

—Captain L. Bilton, 1862, Correspondent of the Mercantile Marine Magazine[6]

1889 rebuild[edit]

Apparatus for the Manora Point Light produced by Chance Brothers and Company

In 1887 designs were proposed for a new lighthouse tower by the Port Engineer’s Office. This was part of a series of ongoing improvements to the harbour, as the port had took on new stage of importance and witnessed a substantial increase in sea traffic, with a constant stream of ships transporting goods and troops to and from the sub-continent.[7]

The lighthouse was completed by 1889 which saw the original tower altered and raised in height almost double the size of the original lighthouse, to a tower standing 91 foot tower. The masonry tower was built was a conical shaped with a lantern and gallery. This tower was painted on the seaward side with red and white horizontal bands; the landward facing side was unpainted.[5]

In 1909 (1908?), a hyperradiant Fresnel lens, produced by the English glassmaking company Chance Brothers, was installed in the tower. Chance Brothers Ltd was one of the major suppliers of lighthouse optical systems in the world, and the only company of its kind in Britain. The lens was considered one of largest and finest in existence, with an inside diameter of 2.66 metres which "revolving lens unit weighed 6 tons but floated on mercury such that it could be turned with one finger."[8][9]

one and a half million candlepower flash every seven and a half seconds. (white flash every 7.5 s.)[9]

It has a focal plane of 48 m (147 ft) with a white flash every 7.5 s. 38 m (125 ft).[5]

"At the time of commissioning the lighthouse probably employed oil lanterns as beacons. Subsequently, the oil lanterns were replaced by electric beacons, which were capable of emitting distinctive series of flashes to help the captains of the incoming ships to identify the lighthouse."

Current site[edit]

The lighthouse is currently active. It is the lighthouse featured on the logo of the Karachi Port Trust. The site is operated by the Karachi Port Trust and while the site is open to the public the tower is closed and inaccessible. The Pakistan Maritime Museum in Karachi has a replica of this lighthouse where the tower can be climbed. However it has been suggested the replica bares little resemblance to the original.[10]

References[edit]

  1. ^ The architect and contract reporter: a weekly illustrated journal of art, civil engineering and building. 1869. p. 130. Retrieved 15 February 2012. 
  2. ^ a b c d "Monthly nautical magazine, and quarterly review, Volume 2". Griffiths, Bates. 1855. pp. 72–73. 
  3. ^ "The Architect, Volume 1". Gilbert Wood. 1869. p. 130. 
  4. ^ a b c Ken Trethewey (2011-10-02). "India - Pharology". Pharology.eu. Retrieved 2011-12-02. 
  5. ^ a b c "Manora Point Light". Lighthouse Explorer Database. Foghorn Publishing. Retrieved 2011-11-25. 
  6. ^ Rosser, William Henry; Imray, James Frederick (1867). "The seaman's guide to the navigation of the Indian Ocean and China Sea". J. Imray & Son. p. 405. 
  7. ^ "Manora Light House and Fort, Karachi". The British Library. 2003-11-30. Retrieved 2011-06-06. 
  8. ^ Talbot, Frederick Arthur Ambrose (1913), Lightships and lighthouses, W. Heinemann, pp. 40–49 
  9. ^ a b "More Comments on Chance Lights". Uklighthouse.info. 2003-02-20. Retrieved 2011-12-02. 
  10. ^ "Lighthouses of Pakistan". Unc.edu. Retrieved 2011-05-08.