Conrad's inhibitions prior to setting off to "Hell"

"After this I got embraced, told to wear a flannel, be sure to write often and so on---and I left. In the street---I don't know why--a queer feeling came to me that I was an impostor. Odd thing, that I, who used to clear out for any part of the world at twenty-four hours' notice with less thought than most men give to the crossing of a street, had a moment--I won't say of hesitation, but of startled pause before this commonplace affair. The best way I can explain it to you is that by saying for a second or two I felt as though instead of going to the centre of a continent I were about to set off for the centre of the earth."
(Joseph Conrad, Heart of Darkness, Ch. 1)

I found this passage an entrancing view into Joseph Conrad's psyche. HIs fear of the unknown river he initially finds so entrancing. mixed with the thoughts and ideas he begins to have after his "inner sanctum" contract agreement. Facing the facts that he most likely will not make it back to his homeland alive along with the truth, being that he is replacing a ship captain who found himself in a sticky situation with the "natives/savages/heathens."