Wood and stone were the earliest materials used in house-building; but as great part of England affords no stone fit for building, her oak-forests were thinned, and less durable dwellings were erected with inferior timber. Stone houses are, however, mentioned as belonging to the citizens of London, even in the latter half of the twelfth century. Flints bound together with strong cement were employed in building manor-houses. Hewn stone was employed for castles, and the larger mansions: much stone was, in early times, brought from Normandy. Chestnut was much employed. Evelyn, in his _Sylva_, states that "The chestnut is, next the oak, one of the most sought after by the carpenter and joiner. It hath formerly built a good part of our ancient houses in the City of London, as does yet appear. I had once a very large barn near the City, framed entirely of this timber; and certainly the trees grew not far off, probably in some woods near the town; for in that description of London, written by Fitz-Stephen, in the reign of Henry II. he speaks of a very noble and large forest which grew on the boreal [north] part of it."[39] Ducarel, in his _Anglo-Norman Antiquities_, says: "Rudhall, near Ross, in Herefordshire, is built with chestnut, which probably grew on the estate, although no tree of the kind is now to be found growing wild in that part of the country. The old houses in the city of Gloucester are constructed of chestnut, derived assuredly from the chestnut-trees in the forest of Dean. In some of the oldest houses of Faversham much genuine chestnut as well as oak is employed. In the nunnery of Davington, near Faversham (now entire), the timber consists of oak, intermingled with chestnut."