1407 when one Maurice Plank was given leave to study at Cambridge University for two terms on the understanding that he would appoint an usher to teach in his absence. Soon after foundation, the school moved to the Guildhall in Hill Street. A record from 1446 details how master Jacob Creffen was granted leave by the Bishop of Ely to collect an "adequate salary" from each scholar according to the "praiseworthy, ancient and approved custom". Following the English reformation, the Guild of the Holy Trinity was dissolved and replaced by the Wisbech Corporation. The school was renamed and re-established by King Edward VI in 1549, who gave the school a charter "for the instruction of youth in grammatical knowledge and polite literature". The charter is still in existence, and is currently held by the Wisbech Museum. The same year, land was given for the construction of a school house next to the Guildhall building. After the Restoration of Charles II, the school's charter was renewed with the stipulation that the Capital Burgesses be given the choice of schoolmaster and that the Bishop of Ely "forever shall have the right of visitation, reformation, and correction of the schoolmaster, as of the school aforesaid". In 1638 a benefactor, William Holmes, gave £400 to the burgesses of Wisbech to be invested in land, and the rest applied for the maintenance of two scholars at Magdalene College, Cambridge. In his will of 1656 Holmes directed that the whole yearly income of his 46-acre estate in Holbeach, Lincolnshire be paid yearly towards the maintenance of the scholars and the endowment of the school. Other land and property had been donated to the school in the wills of Thomas Parkes in 1628 and John Crane in 1651. Crane's estate included land in Fleet, Lincolnshire and an inn on Market Hill called the Black Bull. In 1793, property developer Joseph Medworth purchased the site of Wisbech Castle, including John Thurloe's 1660 mansion (supposedly in a very poor condition) and the land surrounding it from the See of Ely, building the Georgian Circus along the bailey walls. As part of his scheme, in 1811 he tried to persuade the corporation to purchase the mansion and demolish the Old Grammar School building in Ship Street (now Hill Street) with the intention of building a new street through to the market place. The Corporation refused (it is usually assumed that