France Livres De Raison (Family Account Books)

Definition
A livre de raison (from the Latin liber rationis or liber rationum, that is to say "book of accounts") is a register of domestic accounting also including family or local notations. Held by the father, it was a reminder for the author, but it was primarily intended to inform his heirs. Frequently, the same book of reason was transmitted from generation to generation, each head of family holding it in turn. Wikipedia

Content
These books were essentially family account books, usually of farms or businesses, but sometimes of shops. Often, they span centuries and can contain an extraordinary amount of detail, including:
 * Running accounts
 * Copies of bills paid for all sorts of items or services, including veterinaries
 * Copies of wills
 * Copies of baptism, birth, marriage, death and burial registrations
 * Lists of heirs
 * Maps of lands
 * Property ownership histories
 * Notes on local events and/or catastrophes
 * Pages from almanacs