To United States Brig Enterprize, Isaac HULL, Esq., Portland, September 7th, 1813. United States Navy Yard, Portsmouth. Sir: In consequence of the unfortunate death of Lieutenant-Commander William Burrows, late commander of this vessel, it devolves on me to acquaint you with the result of our cruize. After sailing from Portsmouth on the 1st instant, we steered to the eastward, and on the morning of the 3d, off Wood Island, discovered a schooner, which we chased into this harbour, where we anchored. On the morning of the 4th weighed anchor and swept out, and continued our cruize to the eastward. Having received information of several privateers being off Manhagan, we stood for that place; and on the following morning, in the bay near Penguin Point, discovered a brig getting under weigh, which appeared to be a vessel of war, and to which we immediately gave chase. She fired several guns and stood for us, having four ensigns hoisted. After reconnoitering and discovering her force, and the nation to which she belonged, we hauled upon a wind to stand out of the bay, and at 3 o'clock shortened sail, tacked and ran down with an intention to bring her to close action. At 20 minutes after 3 P.M., when within half pistol shot, the firing commenced from both, and after being warmly kept up, and with some manoeuvering, the enemy hailed and said they had surrendered, about 4 P.M. Their colours being nailed to the masts, could not be hauled down. She proved to be His Britannic Majesty's brig Boxer, of 14 guns, Samuel Blythe, Esquire, commander, who fell in the early part of the engagement, having received a cannon shot through the body. And I am sorry to add that Lieutenant Burrows, who had gallantly led us to action, fell also about the same time by a musket ball, which terminated his existence in eight hours. The Enterprize suffered much in spars and rigging, and the Boxer both in spars, rigging and hull, having many shots between wind and water. It would be doing injustice to the merit of Mr. Tillinghast, 2d lieutenant, were I not to mention the able assistance I received from him during the remainder of the engagement, by his strict attention to his own division and other departments. And the officers and crew, generally, I am happy to add, from their cool and determined conduct, have my warmest approbation and applause. As no muster roll that can be fully relied on came into my possession, I cannot exactly state the number killed on board the Boxer; but from information received from the officers of that vessel, it appears that there are between twenty and twenty-five killed, and fourteen wounded. Enclosed is a list of killed and wounded on board the Enterprize.