'A Booke of Lieutenancie wherein is entred all lers directed to the L: Lieuteant of the County of Essex, concerninge Musters or Levyinge of forces, with all such proceedinges as have beene done and executed upon the said lers by his deputy Lieuteants' (p. 13). This is a letter-book of the deputy lieutenants of the county of Essex, 1608-31 and 1638-9, in which are entered all letters of the privy council to the lord lieutenant and deputy lieutenants, of the lord lieutenant to the deputy…