Watching despondent Richard Alpert at the Black Rock, and his admission that this was the first time that he had visited the ship since it had landed, cemented an idea I've had for a while that Richard had come to the island at some point much further in the past than an initial trip on a dynamite-laden vessel. I think Richard's attitude towards his Black Rock voyage reeks of guilt, not what I'd expect from a man who, according to Flocke, had once been in chains.
I think that the Black Rock was a proxy ship for an earlier voyage to the island where Richard first met Jacob and the MIB and where he first received Jacob's touch. In this first voyage to the island, I suspect that Richard was a slave in chains, on a ship with other slaves and his masters. Adventures ensued and at some point in time, Richard had to leave the island with no known means of returning until the Black Rock voyage.
On the Black Rock, Richard took on a different proxy role, as a master of the ship, with others chained up for his benefit so he could return to the island. Dynamite was patented by Richard Nobel in 1867 and by then the international slave trade had mostly ended. Is it possible that an old slave ship was acquired to mimic a Roman ship from which slave Ricardus first encountered the island?