Though the old buildings have been largely swept away, or altered and added to, yet enough remains to enable us, with the help of a fifteenth-century plan, to constitute with some degree of exactness the arrangement of the old monastery. This plan, which is still preserved amongst the archives of the Charterhouse, is a vellum roll ten feet long, of four skins, showing the construction of a conduit by which the monastery was supplied with water from Islington. The waterpipe discharged into a conduit in the centre of the great cloister; from the conduit it was conveyed through the gardens into the cells of the monks. The playground of the Merchant Taylors' School occupies nearly the site of the great cloister, and on the east and the west side of it may be found traces of two of the cells. The lower part of the gatehouse served as entrance to the monastery, though the doors were probably renewed after the Carthusians had gone. The south and part of the east walls of the present chapel are those of the monks' church, and the lower part of the Tower was built by them probably in 1510-20. The charming little quadrangle, known as Wash House Court, was the habitation of the "conversi" or lay brothers, the servants of the convent. On the west external wall of this court are the letters J. H., which may possibly be the initials of the last Prior, John Houghton, and the wall itself of his building. Besides these remains there may also be seen a bit of the monastic refectory, now used as the brothers' library, though it has been thought by some that this is the site of the prior's cell. II.--THE PALACE, 1545-1611 During the period from 1545-1611 the Charterhouse became a nobleman's palace, and passed through several changes of ownership. After the suppression of the monastery the buildings were used as a storehouse for the King's hales (that is, nets) and tents. John Brydges, yeoman, and Thomas Hales were placed in charge of the King's property. This arrangement, however, was of short duration, for in 1545 the King presented the site to Sir Edward North, Brydges and Hales receiving L10 per annum by way of compensation. According to Bearcroft[67] the gift was likely to have cost North dear. The historian tells the story on the authority of one of North's attendants: