Class overview
Name	Mariz e Barros
Builders	J. and G. Rennie, Millwall, London
Preceded by	Bahia
Succeeded by	Cabral class
Built	1864–66
In service	1866–97
Completed	2
Scrapped	2
General characteristics
Class and type	Armored corvette
Displacement	1,196–1,353 long tons (1,215–1,375 t)
Length	191 ft (58.2 m)
Beam	36 ft (11.0 m)
Draft	8.16–9.5 ft (2.5–2.9 m)
Installed power	600 ihp (450 kW)
Propulsion	2 shafts; 2 steam engines
Speed	9 knots (17 km/h; 10 mph)
Armament	4 × 120-pounder Whitworth rifled muzzle-loading guns or 2 × 120-pounder Whitworth guns 2 × 68-pounder smoothbore guns
Armor	Belt: 3–4.5 in (76–114 mm)

The Mariz e Barros-class ironclads were a pair of armored corvettes originally ordered by Paraguay in 1864, but were sold to Brazil when Paraguay defaulted on the payments. Configured as central-battery ironclads, they served during the 1864–70 Paraguayan War between Brazil, Argentina and Uruguay against Paraguay. They were named after Antônio Carlos de Mariz e Barros (1835–1866), son of Joaquim José Inácio, Viscount of Inhaúma, Brazilian military officer and hero of the Paraguayan War.

Design and description

The ships were 191 feet (58.2 m) long, had a beam of 36 feet (11.0 m) and drafts of 8.16–9.5 feet (2.5–2.9 m). They displaced 1,196–1,353 long tons (1,215–1,375 t). The Mariz e Barros class had a pair of steam engines, each driving one propeller. The engines produced a total of 600 indicated horsepower (450 kW) and gave the ships a maximum speed of 9 knots (17 km/h; 10 mph). They carried 140 tonnes (138 long tons) of coal although nothing is known about their range or endurance. They were fully rigged with three masts. Their crew consisted of 125 officers and enlisted men.^[1]

Mariz e Barros was armed with two 120-pounder Whitworth rifled muzzle-loading guns and two smoothbore 68-pounder guns, while Herval had four 120-pounder guns. The ships had a complete waterline belt of wrought iron that ranged in thickness from 114 millimeters (4.5 in) amidships to 76 millimeters (3.0 in) at the ends of the ship.^[1]

Ships