The Brazilian monitor ''Piauí'' was the fourth ship of the river

monitor Monitor or monitor may refer to: Places * Monitor, Alberta * Monitor, Indiana, town in the United States * Monitor, Kentucky * Monitor, Oregon, unincorporated community in the United States * Monitor, Washington * Monitor, Logan County, Wes ...

s built for the

Brazilian Navy The Brazilian Navy () is the navy, naval service branch of the Brazilian Armed Forces, responsible for conducting naval warfare, naval operations. The navy was involved in War of Independence of Brazil#Naval action, Brazil's war of independence ...

during the

Paraguayan War The Paraguayan War (, , ), also known as the War of the Triple Alliance (, , ), was a South American war that lasted from 1864 to 1870. It was fought between Paraguay and the Triple Alliance of Argentina, the Empire of Brazil, and Uruguay. It wa ...

in the late 1860s. ''Piauí'' passed the fortifications at

Humaitá Humaitá is a List of cities and towns in Paraguay, town and Districts of Paraguay, district on the Paraguay River in southern Paraguay. During the Paraguayan War, it served as the main Paraguayan stronghold from 1866 until its fall in August 186 ...

in July 1868 and provided fire support for the army for the rest of the war. The ship was assigned to the

Mato Grosso Mato Grosso ( – ) is one of the states of Brazil, the List of Brazilian states by area, third largest by area, located in the Central-West Region, Brazil, Central-West region. The state has 1.66% of the Brazilian population and is responsible ...

Flotilla A flotilla (from Spanish, meaning a small ''flota'' ( fleet) of ships), or naval flotilla, is a formation of small warships that may be part of a larger fleet. Composition A flotilla is usually composed of a homogeneous group of the same cla ...

after the war. ''Piauí'' was

scrapped Scrap consists of recyclable Recycling is the process of converting waste materials into new materials and objects. This concept often includes the recovery of energy from waste materials. The recyclability of a material depends on i ...

in 1893.

Design and description

The ''Pará''-class monitors were designed to meet the need of the Brazilian Navy for small, shallow-draft armored ships capable of withstanding heavy fire. The monitor configuration was chosen since a turreted design did not have the same problems engaging enemy ships and fortifications as did the central battery ironclads already in Brazilian service. The

oblong An oblong is an object longer than it is wide, especially a non-square rectangle. Oblong may also refer to: Places * Oblong, Illinois, a village in the United States * Oblong Township, Crawford County, Illinois, United States * A strip of land ...

gun turret A gun turret (or simply turret) is a mounting platform from which weapons can be fired that affords protection, visibility and ability to turn and aim. A modern gun turret is generally a rotatable weapon mount that houses the crew or mechanis ...

sat on a circular platform that had a central pivot. It was rotated by four men via a system of gears; 2.25 minutes were required for a full 360° rotation. A bronze

ram Ram, ram, or RAM most commonly refers to: * A male sheep * Random-access memory, computer memory * Ram Trucks, US, since 2009 ** List of vehicles named Dodge Ram, trucks and vans ** Ram Pickup, produced by Ram Trucks Ram, ram, or RAM may also ref ...

was fitted to these ships as well. The hull was sheathed with

Muntz metal Muntz metal (also known as yellow metal) is an alpha-beta brass alloy composed of approximately 60% copper, 40% zinc and a trace of iron. It is named after George Fredrick Muntz, a metal-roller of Birmingham, England, who commercialised the al ...

to reduce

biofouling Biofouling or biological fouling is the accumulation of microorganisms, plants, algae, or small animals where it is not wanted on surfaces such as ship and submarine hulls, devices such as water inlets, pipework, grates, ponds, and rivers that ...

.Gratz, p. 153 The ships measured

long overall Length overall (LOA, o/a, o.a. or oa) is the maximum length of a vessel's hull measured parallel to the waterline. This length is important while docking the ship. It is the most commonly used way of expressing the size of a ship, and is also u ...

, with a

beam Beam may refer to: Streams of particles or energy *Light beam, or beam of light, a directional projection of light energy **Laser beam *Radio beam *Particle beam, a stream of charged or neutral particles **Charged particle beam, a spatially lo ...

of . They had a

draft Draft, the draft, or draught may refer to: Watercraft dimensions * Draft (hull), the distance from waterline to keel of a vessel * Draft (sail), degree of curvature in a sail * Air draft, distance from waterline to the highest point on a v ...

of and displaced . With only of

freeboard In sailing and boating, a vessel's freeboard is the distance from the waterline to the upper deck level, measured at the lowest point of sheer where water can enter the boat or ship. In commercial vessels, the latter criterion measured relativ ...

they had to be towed between Rio de Janeiro and their areas of operations. Their crew numbered 43 officers and men.Gratz, p. 154

Propulsion

The ''Pará''-class ships had two direct-acting

steam engines A steam engine is a heat engine that performs Work (physics), mechanical work using steam as its working fluid. The steam engine uses the force produced by steam pressure to push a piston back and forth inside a Cylinder (locomotive), cyl ...

, each driving a single propeller. Their engines were powered by two tubular

boiler A boiler is a closed vessel in which fluid (generally water) is heated. The fluid does not necessarily boil. The heated or vaporized fluid exits the boiler for use in various processes or heating applications, including water heating, centra ...

s at a working pressure of . The engines produced a total of which gave the monitors a maximum speed of in calm waters. The ships carried enough coal for one day's steaming.

Armament

''Piauí'' had a single 120-pounder Whitworth rifled muzzle loader (RML) in her gun turret. The gun had a maximum range of about . Its shells weighed and the gun itself weighed . Most unusually the gun's Brazilian-designed iron

carriage A carriage is a two- or four-wheeled horse-drawn vehicle for passengers. In Europe they were a common mode of transport for the wealthy during the Roman Empire, and then again from around 1600 until they were replaced by the motor car around 1 ...

was designed to pivot vertically at the muzzle; this was done to minimize the size of the

gunport A gunport is an opening in the side of the hull of a ship, above the waterline, which allows the muzzle of artillery pieces mounted on the gun deck to fire outside. The origin of this technology is not precisely known, but can be traced back to t ...

through which splinters and shells could enter.Gratz, p. 155

Armor

The hull of the ''Pará''-class ships was made from three layers of wood, with the grain of each layer at right angles to the next layer. It was thick and was capped with a layer of peroba hardwood. The ships had a complete

wrought iron Wrought iron is an iron alloy with a very low carbon content (less than 0.05%) in contrast to that of cast iron (2.1% to 4.5%), or 0.25 for low carbon "mild" steel. Wrought iron is manufactured by heating and melting high carbon cast iron in an ...

waterline belt, high. It had a maximum thickness of 102 millimeters amidships, decreasing to and at the ship's ends. The curved deck was armored with of wrought iron. The rectangular gun turret had rounded corners. It was built much like the hull, but the front of the turret was protected by of armor, the sides by 102 millimeters and the rear by 76 millimeters. Its roof and the exposed portions of the platform it rested upon were protected by 12.7 millimeters of armor. The armored

pilothouse A bridge (also known as a command deck), or wheelhouse (also known as a pilothouse), is a room or platform of a ship, submarine, airship, or spacecraft, spaceship from which the ship can be commanded. When a ship is under way, the bridge is manne ...

was positioned ahead of the turret.

Service

''Piauí'' was laid down at the Arsenal de Marinha da Côrte in

Rio de Janeiro Rio de Janeiro, or simply Rio, is the capital of the Rio de Janeiro (state), state of Rio de Janeiro. It is the List of cities in Brazil by population, second-most-populous city in Brazil (after São Paulo) and the Largest cities in the America ...

on 8 December 1866, during the

, which saw

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

and Brazil allied against

Paraguay Paraguay, officially the Republic of Paraguay, is a landlocked country in South America. It is bordered by Argentina to the Argentina–Paraguay border, south and southwest, Brazil to the Brazil–Paraguay border, east and northeast, and Boli ...

. She was launched on 8 January 1868 and commissioned later that month. Together with the ironclads and , ''Piauí'' passed the weakened Paraguayan fortifications at

on 21 July 1868. She bombarded

Asunción Asunción (, ) is the capital and the largest city of Paraguay. The city stands on the eastern bank of the Paraguay River, almost at the confluence of this river with the Pilcomayo River. The Paraguay River and the Bay of Asunción in the north ...

that same day.Gratz, p. 157 The monitor and a number of Brazilian ironclads bombarded Paraguayan batteries at Angostura, downstream of Asunción, on 28 October, 19 November and 26 November. ''Piauí'', together with her

sister ship A sister ship is a ship of the same Ship class, class or of virtually identical design to another ship. Such vessels share a nearly identical hull and superstructure layout, similar size, and roughly comparable features and equipment. They o ...

s and , broke through the Paraguayan defenses at Guaraio on 29 April 1869 and drove off the defenders.Donato, pp. 186, 300 On 31 August 1869 the monitor unsuccessfully tried to locate and destroy the remnants of the Paraguayan Navy on the

Manduvirá River The Manduvirá River (Spanish: ''Río Manduvirá''; Guarani: ''Ysyry Manduvira'') is a river of Paraguay. It is a tributary of the Paraguay River The Paraguay River (''Ysyry Paraguái'' in Guarani language, Guarani, ''Rio Paraguai'' in Portugues ...

. In the 1880s the ship's armament was reinforced with a pair of machine guns. After the war she was assigned to the Mato Grosso Flotilla and was scrapped in 1893.

Notes

References

* * *

External links

Brief history of ''Piauí''
{{DEFAULTSORT:Piaui Ships built in Brazil 1868 ships Pará-class monitors