Former judge Sir Thomas Littleton wrote a legal textbook describing tenancies in dower; the tenures of socage, knight's service, serjeanty, and burgage; estates in fee simple, fee tail, and fee conditional. For instance, "Also, if feoffment be made upon such condition, that if the feoffor pay to the feofee at a certain day, etc., 800s. forty pounds of money, that then the feoffor may re-enter, etc., in this case the feoffee is called tenant in mortgage, ... and if he doth not pay, then the land which he puts in pledge upon condition for the payment of the money is gone from him for ever, and so dead as to the tenant, etc." Joint tenants are distinguished from tenants in common by Littleton thus: "Joint-tenants are, as if a man be seised of certain lands or tenements, etc., and thereof enfeoffeth two, or three, or four, or more, to have and to hold to them (and to their heirs, or letteth to them) for term of their lives, or for term of another's life; by force of which feoffment or lease they are seised, such are joint-tenants. ... And it is to be understood, that the nature of joint-tenancy is, that he that surviveth shall have solely the entire tenancy, according to such estate as he hath, ..." "Tenants in common are they that have lands or tenements in fee-simple, fee-tail, or for term of life, etc., the which have such lands and tenements by several title, and not by joint title, and neither of them knoweth thereof his severalty, but they ought by the law to occupy such lands or tenements in common pro indiviso, to take the profits in common. ...As if a man enfeoff two joint-tenants in fee, and the one of them alien that which to him belongeth to another in fee, now the other joint-tenant and the alienee are tenants in common, because they are in such tenements by several titles, ..." Judicial Procedure