Six Pará-class River Monitors that were Built During the Paraguayan War

Six Pará-class river monitors were built for the Imperial Brazilian Navy during the Paraguayan War, also known as the War of the Triple Alliance, and participated in several key operations during the conflict. These fighting vessels, like the ten Passaic-class monitors that were constructed for the United States Navy, were built to the same general plan. Thompson, on page 246 of The War in Paraguay, explains that the monitors were built in Rio de Janeiro and that they were propelled by twin screws. The iron plates that protected the hull, Thompson continues, had a depth of 4-inches while the armour protection that surrounded the turret was 6-inches in thickness. Richard Burton, writing in Letter XVII of Letters from the Battle-fields of Paraguay, claims that the iron plates that sheathed the monitors were pitted by the blows of solid shot. Afonso Celso de Assis Figueiredo, Viscount of Ouro Preto and author of A Marinha D'Outr'Ora, provides details about the construction of the ships on Chapter IV. Ouro Preto, on pages 47 and 48, identifies the Arsenal de Marinha do Rio de Janeiro as the shipyard in which the monitors were built. Pará, Rio Grande, Alagoas, Piauhy, Ceará and Santa Catharina are named by the Viscount as six ships of their class. Work commenced on the original five ironclads on the 8th of December, 1866, while the construction of the sixth vessel did not occur until the 22nd of March in the following year. Alberto Amerlan, on page 104 of Nights on the Rio Paraguay, states that the power plants which were installed on the Rio de Janeiro-built monitors were capable of generating 30-horsepower. The noise of the high-pressure steam engine onboard Alagoas, Burton recalls, was similar to that of a steam locomotive. Andrew James Kennedy states that Pará and Alagoas were equipped with 70-pounder Whitworth rifles on page 158 of La Plata, Brazil and Paraguay During the Present War while claiming that Piauhy and Rio Grande were armed with 120-pounder Whitworth guns.

 1) Pará.

Amerlan mentions Pará on pages 104, 106 and 108 of Nights on the Rio Paraguay and provides details of some of the riverine operations in which it participated. Pará, Alagoas, Rio Grande and Piauhy are reported to have arrived on the Paraguay River from Rio de Janeiro while under the command of Commodore Delphim Carlos de Carvalho. The monitors forced the batteries of Curupayty on the 13th of February, 1868, and reinforced the ironclad squadron that lay downriver of Humaitá. Thompson, on page 246 of The War in Paraguay, reports that the monitors suffered minimal damage as they passed the guns. López, having noticed the new arrivals on the river, telegraphed Asunción and ordered a general mobilization of the adult male population. The reinforcement of the armoured squadron, López suspected, would persuade the fleet to force the batteries of Humaitá. López was proven to be right in his suspicions when, at half past two in the morning on the 19th of February, a squadron of six ironclads proceeded towards Humaitá under the cover of darkness. It was preceded, on the 18th, by a naval bombardment of the riverside batteries. A rise in the water level, submerging the chain boom and the torpedoes that threatened to hinder the advance of the squadron, provided a rare opportunity to proceed up the river. Delphim commanded this squadron while Admiral Ignacio, also known as the Baron de Inhauma, remained in charge of the ships further down the river. The ironclads were ordered to move past the batteries in pairs, with each of the Pará-class monitors tethered to one of the larger vessels, and Pará was coupled with Tamandaré as they ran the gauntlet of Paraguayan guns. Pará, Thompson claims on page 247, was among the three ironclads that were most damaged by the Timbó batteries that awaited them further up the river. Amerlan claims that Pará and Tamandaré, which had been last in the procession, underwent repairs at Tayí that lasted several weeks.

2) Rio Grande.

Rio Grande, on page 104 of Nights on the Rio Paraguay, is named by Amerlan as one of four monitors that passed the batteries of Curupayty on the 13th of February. Thompson, on page 249 of The War in Paraguay, states that Rio Grande was among the three ironclads that steamed up the River Paraguay in order to attack Asunción. It is explained that Bahia and Barroso accompanied Rio Grande while Alagoas, Pará and Tamandaré remained at Tayí. The ironclads visited Monte Lindo, a Paraguayan supply base that had been sacked and abandoned by its garrison, and burned the storage sheds that contained nothing other than maggot-ridden beef. Pirabebé, towing a schooner and heading for the Paraguayan capital, was chased along the river by the ironclads and had to burn its own furniture when it ran low on fuel. The steamer, while able to escape its pursuers, was compelled to scuttle the schooner that it had in tow. On the 22nd of February, 1868, the ironclads bombarded Asunción. Little damage was done to the arsenal, Thompson explains on page 250 of his memoir, after Criollo fired three shots at the iron-plated warships and deterred them from advancing. Amerlan, on page 121 of his history of the Paraguayan War, states that Rio Grande was one of three ironclads to the force the Paraguayan batteries at the mouth of the Tebicuary River. Thompson, who commanded the batteries that opposed the monitors at the Island of Fortín, writes about this event on page 163 of his book but does not mention Rio Grande by name. Both Amerlan and Thompson agree that the event occurred on the 24th of July, 1868, and that Silvado was among the monitors to force the batteries on that day. Francisco Felix Pereira Da Costa, on page 40 of Historia da Guerra do Brasil Contra as Republicas do Uruguay e Paraguay, claims that Rio Grande was one of six ironclads to engage the fortified positions at Angostura. The inland port, situated on a bend in the Pikysyry River, occupied a natural defensive position.

3) Alagoas.

The survival of Alagoas, separated from its consort and hammered by the guns of Humaitá as it's under-powered engine struggled against the potent river current, provides some insight into the effectiveness of the design of Pará-class river monitors. Amerlan, on page 104 through to page 109 of Nights on the Rio Paraguay, dedicates an entire chapter to Alagoas and the challenges it faced on the morning of the 19th. The ironclad, Amerlan explains, was tethered to Bahia and the two monitors formed the second of three divisions to force the batteries. Bahia was the flagship of Commodore Delphim, who Amerlan claims was the most senior officer in the squadron, while Alagoas was commanded by Captain-Lieutenant Joaquin Maurity. Kennedy names the same ships and commanders as Amerlan on page 162 of La Plata, Brazil, and Paraguay, during the present war while providing a similar account of the events that unfolded that day. Amerlan and Kennedy agree that the tether which bound the two monitors was severed near the Londres battery while Thompson, on page 247 of The War in Paraguay, claims that the pair were separated further along the river. The monitor, Amerlan and Thompson agree, was pushed backwards by the current during its initial moments of distress but was able to proceed along the river under its own steam. Thompson, on page 247, states that the ironclad was struck 180 times before it rejoined the squadron. Kennedy, on page 163 and 183, claims that the Paraguayans attempted to capture the monitor after it had passed the Humaitá batteries but failed in their endeavor. Amerlan, on 107 and 108, states that the assault was repulsed in five minutes. Thompson, on page 251, claims that López ordered Ygurei and Tacuari to seize the ironclad as it navigated the stretch of river between Timbó and Humaitá. The monitor, however, had moved past Timbó before the steamers had finished preparing for the raid.

4) Piauhy.

Piauhy was the fourth of the Pará-class river monitors to be completed and was also known as Piaby, Pianhy or Piauí in the various source materials. Burton, on pages 343 and 344 of Letters from the Battle-fields of Paraguay, provides details about Piauhy and its classmate Alagoas after he visited the monitors near the abandoned battery of Timbó. The ironclads, the English explorer claims, had retrieved several 32-pounder guns from the Paraguay River which had been discarded by the garrison after they had withdrawn from their positions. The guns, the British writer explains, had been deposited in the river by means of a timber slope. Captain Maurity, at the time in which Burton inspected the ironclads, commanded Alagoas while the superior officer onboard Piauhy was Captain Wandenkolk. Burton mentions the wrecks of two Paraguayan steamers, located near the Isla de Guaycurú, and claims that they had been destroyed by the Brazilian monitors during a previous engagement. Ouro Preto, on Chapter XXV of A Marinha D'Outr'Ora, explains that Piauhy was among a detachment of ironclads that was ordered to force the batteries of Humaitá by the Marquis of Caxias. This engagement occurred on the 21st of July, 1868, and should not be confused with the earlier engagement that occurred on the 19th of February. The purpose of this action, which Ouro Preto details on page 376, was to reinforce the vanguard squadron. Angostura, the Viscount explains on Chapter XXVI, was bombarded by the Allies and Piauhy participated in this action. The Brazilian aristocrat, on page 393, claims that the monitor sustained damage to its turret and its bow during one heated exchange with the Angostura batteries. A controversial event, which the Viscount details on Chapter XXVII, involving Piauhy occurred in the December of 1868. The monitor, corresponding with the Paraguayans under a flag of truce, was fired upon by the Angostura batteries and struck six times.

5) Ceará.

Da Costa, on pages 350 and 351 of Historia da Guerra do Brasil Contra as Republicas do Uruguay e Paraguay, mentions that Ceará protected the forces that were under the command of General Portinho while conducting operations in the Tebicuary River. The monitor, accompanied by its classmate Santa Catharina, also helped to transport the Allied artillery across the river. Ouro Preto, on Chapter XXVIII of A Marinha D'Outr'Ora, describes a naval expedition along the Manduvirá River that occurred during the final phases of the war. Jeronymo Gonçalves, Ouro Preto explains, was placed in command of the expedition. Ceará, along with the monitors Piauhy and Santa Catharina, joined the squadron of Brazilian fighting ships that were sent to navigate this river. The date on which the squadron embarked on its mission is given as the 18th of April, 1869, while the commanding officer of Ceará is named as Lieutenant Machado Dutra. Ouro Preto explains that the expedition fell into difficulties when it encountered a fortified position, complete with river obstructions, at Passo Garayo. A garrison of 900 men and a battery of two field guns awaited the squadron while the creek was blocked by iron chains, vine nets, wooden beams as well as boats and carts that were filled with debris. A pair of torpedoes, as naval mines were known in the nineteenth-century, were included in the riverine obstructions. Jansen Muller, Ouro Preto explains on page 407, struck the torpedoes but the underwater explosive devices failed to detonate. Ceará, in the presence of a number of unprotected launches, was alerted to the danger by Jansen Muller and encountered difficulties after its screw propellers became tangled in the vines. A successful attempt, conducted under fire from nearby rifle pits, to free the entangled monitor was made and the warship was able to proceed. Da Costa, on page 240 of his account of the war, mentions that Jansen Muller warned Ceará about the torpedoes that were hidden beneath the water. 

6) Santa Catharina.

Santa Catharina, named after the state in Southern Brazil, was the final Pará-class river monitor to be completed. The monitor, despite its late entry into the war, played an important role in the closing chapters of the conflict. Ouro Preto, on Chapter IV of A Marinha D'Outr'Ora, provides the dates on which Santa Catharina was laid laid down and completed. Work began on the sixth Pará-class monitor on the 22nd of March, 1867, while the keels of its five classmates had been laid down in the previous December. The ironclad was launched on the 6th of March, 1868, which was almost a month after the original four members of its class had received their baptism of fire at Curupayty and Humaitá. The ship, therefore, was the only monitor of the Pará class to be laid down in 1867 and the sole member of its class not to have entered the shipyard on the same day. It took 346 days, or 19 days short of a year, to complete the monitor. Santa Catharina, along with Piauhy and Ceará, was one of three Pará-class monitors to be launched in 1868 and would serve alongside them later in the war. Da Costa, on pages 170 and 171 of Historia da Guerra do Brasil Contra as Republicas do Uruguay e Paraguay, states that Santa Catharina was sent into the Manduvirá River while the other vessels in the squadron were ordered to remain at the river mouth. The diminutive monitor, with its shallow draft, was able to navigate waterways that the larger gunboats could not. Ouro Preto, on Chapter XVIII of his memoir, writes about the final naval engagements on the rivers of Paraguay. The main objective of these operations, the Viscount explains, was to neutralize the six ships that remained in Paraguayan service. On the 18th of April, 1969, Santa Catharina entered the Manduvirá River in order to extinguish the last sparks of Paraguayan resistance on the waterways. The monitor, under the command of Severiano Nunes, was joined by Ceará and Piauhy while Jansen Muller as well as João das Botas played a supporting role.