sentences:  On 10 August 1512 they engaged a slightly smaller French fleet, and a violent melee known as the Battle of St. Mathieu ensued off the coast of Brest.Knyvett's ship grappled with the Breton command vessel "Cordelière", and was engaged in boarding her when the "Cordelière"'s powder magazine blew up (some say it was deliberately ignited).The two vessels burst into flame.