From Allison

Desire-
In this passage Marlow reveals his admiration towards the Russian trader and his underlying jealously of his ability to conquer the darkness. Marlow considers the Russian to be a bewildering mystery. He has gone deep into the wilderness and has been able to overcome the "darkness". Marlow’s description of the trader conveys his admiration towards him. He describes him as "enthusiastic" and "fabulous"; but is puzzled by "how he had succeeded in getting so far, how he managed to remain- why he did not instantly disappear" (54). To Marlow the Russian is a representation of one who can prevail in the wilderness. However, Marlow is also consumed with envy as well. Through the use of a simile Marlow compares the Russian to a modest and clear flame of truth, and light. The trader wanted nothing from the darkness "but the space to breathe in and push on through"(55) and in return, he achieves the greatness Marlow only hopes for, the ability to pursue through the darkness. He is a man able to conquer all he has encountered and has overcome the horrors. Marlow desires the strength to overcome the heart of darkness and remain collected and strong as a person.