Describe symbolism in Outpost of Progress by Joseph Conrad

In Chapter One, several symbols that foreshadow the destiny of Carlier and Kayerts are introduced. First is the dead artist, lying in a grave on the grounds of the trading station. The symbolism here is explicit--the two European characters are likely to meet the same fate. Over the grave stands a crooked cross. Again, the symbolism is explicit: The cross is a universal symbol of sacrifice and redemption. Standing crookedly, one can infer that there is something amiss. Who is to make the sacrifice and to what end? Who is in need of redemption? How will those things come to pass in the story? One is warned ahead of time that the sacrifice and redemption will not follow the usual, archetypal path.