BL 9.2 inch gun Mk IX - X
Encyclopedia
The BL 9.2 inch guns Mk IX and Mk X were British 46.7 calibres naval and coast defence guns in service from 1899 to the 1950s. They had possibly the longest, most varied and successful service history of any British heavy ordnance.

History

These guns succeeded the 9.2 inch Mk VIII
BL 9.2 inch naval gun Mk VIII
The BL 9.2 inch naval gun Mk VIII was designed for the new cordite propellants and was the first British wire-wound gun of this calibre.-Naval service:It was mounted on the Powerful class cruisers from 1897...

 and increased the bore length from 40 to 46.7 calibres, increasing the muzzle velocity from 2347 feet per second (715.4 m/s) to 2643 feet per second (805.6 m/s).

Mk IX was designed as a coast defence gun, with a 3-motion breech. Only 14 were built, and Mk X introduced in 1900 incorporated a single-motion breech and changed rifling.

The 9.2 inch Mk XI
BL 9.2 inch Mk XI naval gun
The BL 9.2 inch gun Mark XI was a British 50 calibre high-velocity naval gun which was mounted as primary armament on armoured cruisers and secondary armament on pre-dreadnought battleships.-History:...

 gun introduced in 1908 increased the bore length to 50 calibres in an attempt to increase the velocity still further, but proved unsuccessful in service and was phased out by 1920. Mk X was hence the final Mark of 9.2 inch guns in British Commonwealth service.

Design

These were medium velocity wire-wound guns with Welin interrupted screw breeches
Welin breech block
The Welin breech block was a revolutionary stepped, interrupted thread design for locking artillery breeches, invented by Axel Welin in 1889 or 1890...

.

Royal Navy

Mark X guns were mounted on :
  • Cressy class armoured cruisers
    Cressy class cruiser
    The Cressy class cruiser was a class of six armoured cruisers launched between December 1899 and May 1901, for the Royal Navy.-Service:...

     commissioned from 1901
  • Drake class armoured cruisers
    Drake class cruiser
    The Drake-class was a four-ship class of armoured cruisers built around 1900 for the Royal Navy.-Design:The class were enlarged versions of the Cressy class.-History:The ships served in the First World War with only two surviving it...

     commissioned from 1902
  • Duke of Edinburgh class armoured cruisers
    Duke of Edinburgh class cruiser
    The Duke of Edinburgh-class was a class of six armoured cruisers built around 1905 for the British Royal Navy. The later four ships were armed differently, and are sometimes considered as a separate class, the Warrior-class....

     commissioned from 1906
  • King Edward VII class battleships
    King Edward VII class battleship
    The King Edward VII class was a class of pre-dreadnought battleships launched by the Royal Navy between 1903 and 1905.-Armament:By 1901, the 29 British battleships of the Majestic, Canopus, Formidable, London, Queen, and Duncan classes then in service or under construction, all following the same...

     commissioned from 1905
  • M15 class monitor
    M15 class monitor
    The M15-class comprised fourteen monitors of the Royal Navy, all built and launched during 1915.- Design :The ships of this class were ordered in March, 1915, as part of the Emergency War Programme of ship construction...

    s M15, M16, M17, M18 from 1915


Greek Navy

4 guns of 45 calibres (414 inches) bore produced by Elswick Ordnance Company were mounted in 2 twin turrets on the Greek cruiser Georgios Averof
Greek cruiser Georgios Averof
Georgios Averof is a Greek warship which served as the flagship of the Royal Hellenic Navy during most of the first half of the 20th Century...

 in 1910, instead of the 10-inch guns mounted on her sisters of the Pisa class in Italian service. These were similar to the 4 Vickers 45 calibre export model guns used by Britain as railway artillery on the Western Front in World War I under the designation BL 9.2 inch gun Mark XIV. They fired the same 380-pound shell using the same 120-pound cordite charge as the British service Mk X gun, and it may be assumed that its performance was very similar.

British coastal deployments

These guns were 'counter-bombardment' guns designed to defeat ships up to heavy cruisers armed with 8-inch guns. They were deployed in the fixed defences of major defended ports throughout the British Empire until the 1950s.

Their role was to defeat enemy ships attacking the ships in a port, including warships, alongside or at anchor in the port. However, where guns covered narrows, such as the Dover Straits or Straits of Gibraltar, they also had a wider role of engaging enemy ships passing through the straits. Normally deployed in batteries of two or three guns, a few major port had several batteries positioned miles apart.

There were several marks of mountings and a battery had extensive underground facilities in addition to the guns visible in their individual gun-pits. Together with the 6-inch Mk VII, they provided the main heavy gun defence of the United Kingdom in World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

. 3 Mk IX and 53 Mk X guns were in place as at April 1918.

Mounting

The Mounting Barbette Mark V (the original mounting with Mark IX and X guns) gave a maximum elevation of 15 degrees, and maximum range of 21,000 yards. This and some modified to Mark VI (30 degrees and 29,500 yards) were manually powered, the projectile and propelling charge were manually hoisted to loading level, the projectile manually loaded and rammed, and traverse and elevation were by handwheels. There was an elevated platform around the breach area for the gun detachment commander (No 1) and some detachment members, and a gun shield to the front. The ordnance and mounting together weighed some 125 tons, they were well balanced and the handwheels needed very little effort to move the gun.

However, the Mark VII mounting appeared in the 1930s and in 1939 a simplified version, Mark IX. Both were hydraulically powered and the platform was enclosed in a roofed gun house with three sides (and rear with Mark IX). The hydraulics meant that both projectile and propelling charge could be hoisted in a single load. With Mark VII and IX the maximum elevation was increased to 35 degrees to give a maximum range of 36,700 yards.

Installation

Each gun mounting was installed on a central cast-steel pedestal in a open concrete gunpit 35 feet in diameter and 11 feet deep. The gun and mounting weighed 125 tons. A very narrow gauge rail track was embedded around the gunpit floor. A trolley was manhandled around the track between the two ammunition lifts (one for projectiles, one for propelling charges) and the rear of the gun (this position varied depending on where the gun was pointed).

Below the gun pit were the separate ammunition bunkers for projectiles and shells with direct access to the ammunition lifts. These bunkers had an access road leading to them for ammunition re-supply. The guns presented only a very small target above ground level, guns and gunpits were camouflaged.

Organisation

Two or three guns comprised a named battery position with the guns manned by a Heavy Battery. For example in 1940 Madalena and Bijemma Batteries, both with 9.2 in Malta were manned by 6 Heavy Battery RA of 4 Heavy Regiment RA.

Increasing range led to new centralised control arrangements. Fortress observation posts, equipped with rangefinders and directors were sited 4000 – 10,000 yards apart to give observation of all the sea area within range. They reported enemy ship bearings and distances to the ‘Fortress Plotting Centre’ (FPC) where the attackers' positions and courses were plotted, converted to coordinates and then assigned as targets to batteries by the fire commander. The details were telephoned to batteries. The battery plotting room used a Coordinate Converter to turn the coordinates into bearings and elevations and transmitted them to the guns where pointers were matched by changing the guns’ traverse and elevations.

The Observers also reported fall of shot relative to the targets, the FPC used an Encoder to convert these into a Clock Code, which the battery converted to its Left/Right, Add/Drop corrections. Various types of radars integrated into the fire command soon became widespread in WW2 and enabled effective night engagements.

Deployments

The following table summarises the deployment of 9.2 inch guns. It is possible that some 1914 guns were still the older Marks. * indicates deployment was not completed until after 1940. A third Canadian battery was not completed until after World War II.
Ports Defended by 9.2 Inch Guns
Port Country/Territory World War I World War II
Dover United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

5 6
Medway & Thames United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

4 2
Harwich United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

0 2
Tyne United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

2 1
Tees & Hartlepool United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

0 1
Humber United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

0 2
Solent United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

14 6
Portland United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

6 4
Plymouth United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

8 6
Milford Haven United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

4 2
Forth United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

6 3
Lough Swilly Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

2 0
Queenstown Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

4 0
Berehaven Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

2 0
Gibraltar Gibraltar
Gibraltar
Gibraltar is a British overseas territory located on the southern end of the Iberian Peninsula at the entrance of the Mediterranean. A peninsula with an area of , it has a northern border with Andalusia, Spain. The Rock of Gibraltar is the major landmark of the region...

14 8
Freetown Sierra Leone
Sierra Leone
Sierra Leone , officially the Republic of Sierra Leone, is a country in West Africa. It is bordered by Guinea to the north and east, Liberia to the southeast, and the Atlantic Ocean to the west and southwest. Sierra Leone covers a total area of and has an estimated population between 5.4 and 6.4...

2 2
Hamilton
Hamilton, Bermuda
Hamilton is the capital of the British Overseas Territory of Bermuda. It is the territory's financial centre and a major port and tourist destination.-Geography:...

Bermuda
Bermuda
Bermuda is a British overseas territory in the North Atlantic Ocean. Located off the east coast of the United States, its nearest landmass is Cape Hatteras, North Carolina, about to the west-northwest. It is about south of Halifax, Nova Scotia, Canada, and northeast of Miami, Florida...

3 0
Kingston
Kingston, Jamaica
Kingston is the capital and largest city of Jamaica, located on the southeastern coast of the island. It faces a natural harbour protected by the Palisadoes, a long sand spit which connects the town of Port Royal and the Norman Manley International Airport to the rest of the island...

Jamaica
Jamaica
Jamaica is an island nation of the Greater Antilles, in length, up to in width and 10,990 square kilometres in area. It is situated in the Caribbean Sea, about south of Cuba, and west of Hispaniola, the island harbouring the nation-states Haiti and the Dominican Republic...

1 0
Valetta Malta
Malta
Malta , officially known as the Republic of Malta , is a Southern European country consisting of an archipelago situated in the centre of the Mediterranean, south of Sicily, east of Tunisia and north of Libya, with Gibraltar to the west and Alexandria to the east.Malta covers just over in...

16 7
Capetown South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

2 7
Simonstown South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

3 3
Durban
Durban
Durban is the largest city in the South African province of KwaZulu-Natal and the third largest city in South Africa. It forms part of the eThekwini metropolitan municipality. Durban is famous for being the busiest port in South Africa. It is also seen as one of the major centres of tourism...

South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

0 3*
Port Louis
Port Louis
-Economy:The economy is dominated by its port, which handles Mauritius' international trade. The port was founded by the French who preferred Port Louis as the City is shielded by the Port Louis/Moka mountain range. It is the largest container handling facility in the Indian Ocean and can...

Mauritius
Mauritius
Mauritius , officially the Republic of Mauritius is an island nation off the southeast coast of the African continent in the southwest Indian Ocean, about east of Madagascar...

2
Colombo
Colombo
Colombo is the largest city of Sri Lanka. It is located on the west coast of the island and adjacent to Sri Jayawardenapura Kotte, the capital of Sri Lanka. Colombo is often referred to as the capital of the country, since Sri Jayawardenapura Kotte is a satellite city of Colombo...

Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...

4 2
Trincomalee
Trincomalee
Trincomalee is a port city in Eastern Province, Sri Lanka and lies on the east coast of the island, about 113 miles south of Jaffna. It has a population of approximately 100,000 . The city is built on a peninsula, which divides the inner and outer harbours. Overlooking the Kottiyar Bay,...

Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...

0 2
Singapore Singapore
Singapore
Singapore , officially the Republic of Singapore, is a Southeast Asian city-state off the southern tip of the Malay Peninsula, north of the equator. An island country made up of 63 islands, it is separated from Malaysia by the Straits of Johor to its north and from Indonesia's Riau Islands by the...

5 6
Hong Kong Hong Kong
Hong Kong
Hong Kong is one of two Special Administrative Regions of the People's Republic of China , the other being Macau. A city-state situated on China's south coast and enclosed by the Pearl River Delta and South China Sea, it is renowned for its expansive skyline and deep natural harbour...

8 8
Sydney - North Head
Sydney Heads
Sydney Heads , is the entrance to Port Jackson in Sydney, New South Wales, Australia.North Head and Quarantine Head are to the north, South Head and Dunbar Head are to the south. Middle Head, Georges Head and Chowder Head are to the west and within the bay...

Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

0 2
Sydney - Cape Banks Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

0 2
Port Kembla - Drummond Battery
Drummond Battery
Drummond Battery was a counter bombardment battery at Port Kembla, Australia during World War II.Constructed in 1942 to provide protection for Port Kembla from enemy shipping and submarines. Two BL 9.2 inch Mk X gun emplacements with related underground facilities were constructed near Drummond,...

Australia 0 2
Newcastle Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

0 2
Fremantle
Fremantle, Western Australia
Fremantle is a city in Western Australia, located at the mouth of the Swan River. Fremantle Harbour serves as the port of Perth, the state capital. Fremantle was the first area settled by the Swan River colonists in 1829...

 - Rottnest Island
Rottnest Island
Rottnest Island is located off the coast of Western Australia, near Fremantle. It is called Wadjemup by the Noongar people, meaning "place across the water". The island is long, and at its widest point with a total land area of . It is classified as an A Class Reserve and is managed by the...

Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

0 2
Halifax Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

0 3*
Vancouver Island Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

0 2*
Auckland - Stony Batter
Stony Batter
Stony Batter is a historic defence installation at the northeastern end of Waiheke Island, Auckland, New Zealand. It is sited within a 50 acre scenic reserve of the same name, owned by the New Zealand Department of Conservation...

New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

0 2*
Auckland - Whangaparaoa
Whangaparaoa Peninsula
Whangaparaoa Peninsula is a peninsula and suburban area, around 25 km north of Auckland, New Zealand. Part of Rodney District, as of 2006, it had 22,788 residents, many of them in the eponymous town of Whangaparaoa on its southern side.-Geography:...

New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

0 2*
Wellington - Wrights Hill Fortress
Wrights Hill Fortress
Wrights Hill Fortress is a counter bombardment coastal artillery battery in the Karori suburb of Wellington, New Zealand. It was built between 1942 and 1947 and is predominantly underground, with numerous tunnels linking the war shelters, gun emplacements, magazines, plotting rooms and engine room...

New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

0 2*

Deployment on railway trucks

In 1916 Elswick adapted a small number of Mk X guns, 2 Mk X variants originally intended for coast defence in Australia, and 4 45-calibre Vickers export guns (under the designation 9.2 inch gun Mk XIV) and mounted them on Mk 3 railway truck mountings for service on the Western Front
Western Front (World War I)
Following the outbreak of World War I in 1914, the German Army opened the Western Front by first invading Luxembourg and Belgium, then gaining military control of important industrial regions in France. The tide of the advance was dramatically turned with the Battle of the Marne...

 in France and Belgium.

Belgian coast

From 1917 several Mk X guns were deployed ashore on the section of the Belgian coast still held by the Allies, near Nieuport. They were part of the "Royal Naval Siege Guns" under the command of Admiral Sir Reginald Bacon
Reginald Bacon
Admiral Sir Reginald Hugh Spencer Bacon, KCB, KCVO, DSO was an officer in the Royal Navy noted for his technical abilities who was described by the First Sea Lord, Admiral Sir Jacky Fisher, as the man "acknowledged to be the cleverest officer in the Navy".-Family:Reginald was born at Wiggonholt in...

, and were used for attacking German heavy gun batteries.

Other deployments

In the 1950s Canadian guns were transferred, under NATO auspices, to Portugal (Azores) and Turkey. It is unclear if any UK guns were also transferred.

Surviving examples

  • Mk X (ordnance only) Firepower!, Woolwich.
  • Mk X guns at Lord Airey's Battery and O'Hara's Battery, Gibraltar.
  • On Greek cruiser Georgios Averof
    Greek cruiser Georgios Averof
    Georgios Averof is a Greek warship which served as the flagship of the Royal Hellenic Navy during most of the first half of the 20th Century...

     in Faliron Bay near Athens, Greece.
  • Mk X Gun at Imperial War Museum Duxford
    Imperial War Museum Duxford
    Imperial War Museum Duxford is a branch of the Imperial War Museum near the village of Duxford in Cambridgeshire, England. Britain's largest aviation museum, Duxford houses the museum's large exhibits, including nearly 200 aircraft, military vehicles, artillery and minor naval vessels in seven...

     ex Spur Battery, Gibraltar.


Click on the coordinate links in the following list to view map location and/or satellite image.

There are ten guns in the surrounds of Cape Town
Cape Town
Cape Town is the second-most populous city in South Africa, and the provincial capital and primate city of the Western Cape. As the seat of the National Parliament, it is also the legislative capital of the country. It forms part of the City of Cape Town metropolitan municipality...

, South Africa :

Near Simonstown three 9.2 inch guns in the Scala Battery : – entrance to underground power station etc

Above Llandudno three 9.2 inch guns in the Apostle Battery :
On Robben Island
Robben Island
Robben Island is an island in Table Bay, 6.9 km west of the coast of Bloubergstrand, Cape Town, South Africa. The name is Dutch for "seal island". Robben Island is roughly oval in shape, 3.3 km long north-south, and 1.9 km wide, with an area of 5.07 km². It is flat and only a...

 three 9.2 inch guns in the De Waal Battery : (soon to be restored to full operation?)

Near central Cape Town
Cape Town
Cape Town is the second-most populous city in South Africa, and the provincial capital and primate city of the Western Cape. As the seat of the National Parliament, it is also the legislative capital of the country. It forms part of the City of Cape Town metropolitan municipality...

 one 9.2 inch gun in a unique “disappearing mount” in Fort Wynyard :

On the Durban Bluff, South Africa, three 9.2 inch guns in the Da Gama Battery :

On Rottnest Island
Rottnest Island
Rottnest Island is located off the coast of Western Australia, near Fremantle. It is called Wadjemup by the Noongar people, meaning "place across the water". The island is long, and at its widest point with a total land area of . It is classified as an A Class Reserve and is managed by the...

, off Fremantle
Fremantle
Freemantle is a suburb of Southampton in England.Fremantle or Freemantle may also refer to:- Places :* Fremantle, the port city to the capital Perth, Western Australia...

, Western Australia two 9.2 inch guns in the Oliver Hill Battery : – H1 Gun (restored) – H2 Gun (awaiting restoration) – entrance to underground power station etc

British ammunition up to World War I

Shells up to and including World War I were not streamlined, typically having fairly blunt noses of 2 C.R.H..

British World War II ammunition

World War II ammunition was somewhat streamlined, typically with ballistic caps of 4 or 5/10 C.R.H., but still retained square bases rather than the tapered type base typical of projectiles for more modern guns in use in World War II. "Super" charges of 124 pounds cordite SC 205 were available, which boosted the muzzle velocity to 2872 feet per second (875.4 m/s)

External links

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