Tenenda non tollenda, or, The necessity of preserving tenures in capite and by knight-service [electronic resource] : which according to their first institution were, and are yet, a great part of the salus populi, and the safety and defence of the King, as well as of his people : together with a prospect of the very many mischiefs and inconveniences, which by the taking away or altering of those tenures, will inevitably happen to the King and his kingdomes / by Fabian Philipps