The Osprey class was a Royal Navy

Royal Navy

The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

 class of screw-driven sloop

Sloop-of-war

In the 18th and most of the 19th centuries, a sloop-of-war was a warship with a single gun deck that carried up to eighteen guns. As the rating system covered all vessels with 20 guns and above, this meant that the term sloop-of-war actually encompassed all the unrated combat vessels including the...

s built between 1874 and 1877. Nine additional ships were built to a revised design, the . They were the first class of ship in the Royal Navy to use glass scuttle

Scuttle

Scuttle may refer to:*Scuttling, the deliberate sinking of one's own ship*Coal scuttle, a bucket-like container for coal*Shaving scuttle, a teapot-like container for hot water*Scuttle, a fictional character in Disney's The Little Mermaid...

s.

Design

They were of composite construction, with wooden hulls over an iron frame. Five ships of the class were built, which had been designed in 1874 by the Royal Navy

Royal Navy

The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

's Chief Constructor

Director of Naval Construction

The Director of Naval Construction was a senior British civil servant post in the Admiralty, that part of the British Civil Service that oversaw the Royal Navy. The post existed from 1860 to 1966....

, William Henry White

William Henry White

Sir William Henry White was a prolific British warship designer and Chief Constructor at the Admiralty....

. They were the first ships in the Royal Navy to have glass scuttles instead of solid plug scuttles.

Propulsion

The original design, as fitted to the first two ships of the class, was a single-expansion returning-rod steam engine, but the power was insufficient, and they failed to meet the contracted speed. Wild Swan and Penguin were re-engined after their first commission to match the better engines in the rest of the class. In the final installation, power was provided by three cylindrical boilers, which supplied steam at 60 pound per square inches (413,685.4 Pa) to a two-cylinder horizontal compound-expansion steam engine driving a single 13 inch screw. The power varied wildly from ship to ship, with Penguin generating only 666 ihp and Pelican managing nearly twice as much, at 1056 ihp. Because of this, top speeds ranged between 10 and 12 knots.The lower power figures may be the trials figures from the initial installation in Wild Swan and Pelican and should be treated with caution.

Armament

They were armed with two 7-inch (90cwt) muzzle-loading rifled guns on pivoting mounts, and four 64-pounder muzzle-loading rifled guns

RML 64 pounder 64 cwt gun

The RML 64 pounder 64 cwt gun was a Rifled, Muzzle Loading naval, field or fortification artillery gun manufactured in England in the 19th century, which fired a projectile weighing approximately...

 (two on pivoting mounts, and two broadside). Four machine guns and one light gun completed the weaponry. Wild Swan and Pelican later had the muzzle-loading guns replaced with two 6-inch (81cwt) breech-loaders

BL 6 inch 80 pounder gun

The BL 6 inch 80 pounder gun Mk I was the first generation of British 6-inch breechloading naval gun after it switched from muzzle-loaders in 1880. They were originally designed to use the old gunpowder propellants.-Mk I 80-pounder:...

 and six 5-inch (31cwt) breech-loaders.

Sail plan

All the ships of the class were provided with a barque

Barque

A barque, barc, or bark is a type of sailing vessel with three or more masts.- History of the term :The word barque appears to have come from the Greek word baris, a term for an Egyptian boat. This entered Latin as barca, which gave rise to the Italian barca, Spanish barco, and the French barge and...

 rig, that is, square-rigged foremast and mainmast, and fore-and aft sails only on the mizzen mast.

Development

The design was revised in 1877 and nine ships were ordered to a modified version, the . Identical in many respects, the Doterels lacked the graceful clipper bow of the Ospreys, although they benefited from more power.

Ships

Name	Ship Builder	Laid down	Launched	Commissioned	Fate
Wild Swan	Robert Napier Robert Napier (engineer) Robert Napier was a Scottish engineer, and is often called "The Father of Clyde Shipbuilding."-Early life:Robert Napier was born in Dumbarton at the height of the Industrial Revolution, to James and Jean Napier...  and Sons, Govan Govan Govan is a district and former burgh now part of southwest City of Glasgow, Scotland. It is situated west of Glasgow city centre, on the south bank of the River Clyde, opposite the mouth of the River Kelvin and the district of Partick....	14 September 1874	28 January 1876	23 August 1877	Renamed Clyde in 1904 as the Royal Naval Reserve Royal Naval Reserve The Royal Naval Reserve is the volunteer reserve force of the Royal Navy in the United Kingdom. The present Royal Naval Reserve was formed in 1958 by merging the original Royal Naval Reserve and the Royal Naval Volunteer Reserve , a reserve of civilian volunteers founded in 1903...  drill ship at Aberdeen Aberdeen Aberdeen is Scotland's third most populous city, one of Scotland's 32 local government council areas and the United Kingdom's 25th most populous city, with an official population estimate of .... . Renamed Columbine in 1912. Sold for breaking up 4 May 1920
Penguin HMS Penguin (1876) HMS Penguin was an Osprey-class sloop. Launched on 1876, Penguin was operated by the Royal Navy from 1877 to 1881, then from 1886 to 1889...	Robert Napier and Sons, Govan	14 July 1874	25 March 1876	23 August 1877	Sold as a crane hulk Hulk (ship) A hulk is a ship that is afloat, but incapable of going to sea. Although sometimes used to describe a ship that has been launched but not completed, the term most often refers to an old ship that has had its rigging or internal equipment removed, retaining only its flotational qualities...  1924, burnt out 13 December 1960
Osprey	Sheerness Dockyard Sheerness Sheerness is a town located beside the mouth of the River Medway on the northwest corner of the Isle of Sheppey in north Kent, England. With a population of 12,000 it is the largest town on the island....	1875	5 August 1876	19 April 1877	Sold for breaking Ship breaking Ship breaking or ship demolition is a type of ship disposal involving the breaking up of ships for scrap recycling. Most ships have a lifespan of a few decades before there is so much wear that refitting and repair becomes uneconomical. Ship breaking allows materials from the ship, especially...  29 April 1890
Pelican	Devonport Dockyard HMNB Devonport Her Majesty's Naval Base Devonport , is one of three operating bases in the United Kingdom for the Royal Navy . HMNB Devonport is located in Devonport, in the west of the city of Plymouth in Devon, England...	8 March 1875	26 April 1877	29 November 1877	Sold as a supply ship 22 January 1901
Cormorant HMS Cormorant (1877) HMS Cormorant was an Osprey-class sloop launched at Chatham on 12 September 1877 and later the receiving ship at Gibraltar. She was renamed Rooke in 1946 and broken up in 1949.-Design:...	Chatham Dockyard Chatham Dockyard Chatham Dockyard, located on the River Medway and of which two-thirds is in Gillingham and one third in Chatham, Kent, England, came into existence at the time when, following the Reformation, relations with the Catholic countries of Europe had worsened, leading to a requirement for additional...	1875	12 September 1877	2 July 1878	Harbour hulk Hulk (ship) A hulk is a ship that is afloat, but incapable of going to sea. Although sometimes used to describe a ship that has been launched but not completed, the term most often refers to an old ship that has had its rigging or internal equipment removed, retaining only its flotational qualities...  November 1889, renamed Rooke July 1946. Scrapped at Malaga Málaga Málaga is a city and a municipality in the Autonomous Community of Andalusia, Spain. With a population of 568,507 in 2010, it is the second most populous city of Andalusia and the sixth largest in Spain. This is the southernmost large city in Europe... in 1949