Who is Captain Joel Chase from Sharpe's Trafalgar: Richard Sharpe and the Battle of Trafalgar, October 21, 1805 and what is their importance?

Captain Joel Chase is very like Richard Sharpe in both manners and personality. Chase is the commander of the Calliope, the ship that rescues Sharpe and the others from pirates. He is determined to make a name for himself in the navy, and his men are loyal to him because he is a fairminded captain. Chase is aware of Sharpe's affair with Lady Grace but warns Sharpe to be careful that the situation doesn't create a problem aboard his ship.