La Plata
This 1858 despatch reports that the La Plata is to be detained until the arrival of the Queen's Messenger from Osborne, at the behest of Lytton. And, another 1858 despatch, in an enclosure, suggests that the La Plata was commanded at the time by one Captain Meller, who appears as one node in a web of communications critical to the conveyance of the Royal Engineers to the Vancouver Island.
On January 26th, 1867, The Lancet reports that another of the Royal West Indian Mail Company's steam ships, (La Plata) arrived in Southampton from Saint Thomas bursting with yellow fever.1
Perhaps this is the same La Plata that The New York Times reported sunk in the Bay of Biscay in 1875.2 Boatswain Henry Lamont and quarter-master John Hooper were reported rescued from a makeshift raft three days after the La Plata foundered.3
The Ships List notes that the first Arabia, 1852, was renamed La Plata while under construction.4
Mentions of this vessel in the documents