This time the passage was carried out by the new Brazilian monitors Alagoas, Pará and Rio Grande, in addition to some other wooden ships.

[1] The fortress itself would only be abandoned on 23 March 1868, so the Paraguayans were still stationed there and any attempt to overtake it would also be under artillery fire.

The Brazilian government had already made the decision to force the passage of the fortress of Humaitá, which effectively happened six days later on 19 February 1868,[2] and for this feat it was necessary to force the passage of Curupayty once again, since the new flotilla would have to join the other fleet trapped between the two fortresses.

However, due to a mechanical failure and a collision between Alagoas and Ipiranga that brought down the funnel onto its deck, the passage attempt was halted.

[8] The wooden ships responded to fire from the Paraguayan garrison, with Alagoas and Pará advancing shortly thereafter at 21:30.