How does Bernard Cornwell use imagery in Sharpe's Trafalgar: Richard Sharpe and the Battle of Trafalgar, October 21, 1805?

Imagery:

"The men don't think you're a proper officer, and the other officers ... well, it's like a working dog ending up on the hearth rug. The lap dogs don't like it."

"That you would follow him into the throat of hell? By God sir, I'd follow that man into the belly of hell and down to its bowels too."