673. In the last year of the seventeenth century appeared a curious work, entitled Fruit-walls improved by inclining them to the Horizon, by N. Facio de Duillier, F. R. S. This work incurred the censure of the practical authors of the day; but, founded on correct mathematical principles, it attracted the attention of the learned, and of some noblemen. Among the latter was the Duke of Rutland; and the failure of the trial of one of these walls led to the earliest example which we have been able to discover of forcing grapes in England. This, Lawrence and Switzer agree, was successfully accomplished at Belvoir Castle, in 1705. The slanting walls were revived in some places in 1848.