Woolf describes Oliver's physical appearance at the beginning of the short story. As part of this description she compares his nose, "which [is] long and flexible," to "an elephant's trunk." She then describes how he always seems to be sniffing after something and compares him to "a giant hog in a pasture rich with truffles."
A little later in the story, Woolf compares the way that Oliver walks to the walk of "the camel at the zoo." Woolf develops this comparison by equating the camel's haughty, dissatisfied demeanor as it walks "along the asphalt paths" with Oliver's demeanor as he strides down Piccadilly toward his little shop by Bond Street.
Later, when Oliver is examining some jewels, he throws his head back and makes "a sound like a horse neighing." This image conveys the pleasure that Oliver takes in this particular task.
The frequent comparisons to animals are not especially flattering and altogether have the effect of dehumanizing Oliver. This suggests that perhaps Woolf did not want us to sympathize with this character; at the end of the story, his greed gets the better of him.