18th Century Portrait of a Gentleman and his Hound

A large 18th century portrait of a gentleman from the circle of Richard Van Bleek (c.1670-1733).  The gentleman shown in three-quarter-length, holding a gun in his left hand, a dog to his side, with a partridge and casket of gun-powder on a ledge and with an extensive landscape beyond.
Indistinctly signed and dated ‘1731’ on the dog’s collar
oil on canvas, unframed