Lost At Sea.— We regret to announce the death of Robert McDonald, son of Charles McDonald of this town, who was lost overboard from the brig Conquest, Capt Scott, of Yarmouth, on the 11th of November last, on the voyage from New York to Antwerp.  He fell from the maintop gallant yard, and altho' the vessel was hove to, the boat cut away and instantly manned by four of the crew, their efforts to save him proved unavailing, as he sank and disappeared for the last time ere the boat could reach him. Mr McDonald was in his 24th year, was an amiable and worthy young man, and his untimely end has cast a heavy gloom over his family, to whom he had endeared himself by his affectionate conduct as a son and a brother. — Eastern Chron.