Answer:
to create a picture of a fine English gentleman.
Step-by-step explanation:
Joseph Conrad uses characterization as a literary to highlight the details of the white man thoroughly. He mentions details like "high starched collar, white cuffs, a lightalpaca jacket, snowy trousers.." to create a picture of a fine English gentleman.
This characterization helps the readers to perceive how a white man from the British Empire actually looked like and how luxurious and admirable a person from Britain was. The minute details of the white man help the readers perceive Britain as a powerful and rich country.