An oast is a building specifically designed for drying hops. These, if you look directly at the cowls, show the initials of the four sons of Edward Hussey III, Edward, William, Arthur and Henry. Another cloudy day so it is not easy to see them through the lens.
@cottiac I walk on the estate but this time, because I took the photo, I thought I should read the signs put up by the National Trust- an education for me too - when I got home I looked them up - so close to home but knew so little!!