On lookout

Massive statues on the FCO building at the corner of King Charles Street and Horse Guards Road in Whitehall. Who are these solemn characters? I think the bearded gent is probably Poseidon, I think that's some sort of oar in his hand. Or maybe he's Old Father Thames (but he's facing away from the river). To his left looks like a young Queen Victoria to me. I've no idea who's on his right, presumably another British Queen? Maybe somebody I Blipland can enlighten me, I've Googled for an answer but got nowhere, alas.

All I know is they are keeping a stern lookout.