There was a great expansion of arable land. Some land had been specifically allocated to certain individuals. Some was common land, held by communities. If a family came to pay the dues and fines on certain common land, it could become personal to that family and was then known as heirland. Most land came to be privately held from community-witnessed allotments or inheritance. Bookland was those holdings written down in books. This land was usually land that had been given to the church or monasteries because church clerics could write. So many thegns gave land to the church, usually a hide, that the church held 1/3 of the land of the realm. Folkland was that land that was left over after allotments had been made to the freemen and which was not common land. It was public land and a national asset and could be converted to heirland or bookland only by action of the king and witan. It could also be rented by services to the state via charter. A holder of folkland might express a wish, e.g. by testamentary action, for a certain disposition of it, such as an estate for life or lives for a certain individual. But a distinct act by the king and witan was necessary for this wish to take effect. Small private transactions of land could be done by "livery of seisin" in the presence of neighbors. "Seisin" is rightful possession. A man in possession of land is presumed to have "seisin", unless and until someone else can establish a better title by legal process. All estates in land could be let, lent, or leased by its holders, and was then known as "loenland". Ploughs and wagons could be drawn by four or more oxen or horses in sets of two behind each other. Oxenshoes and horseshoes prevented lameness due to cracked hooves. Horse collars especially fitted for horses, replaced oxen yoke that had been used on horses. The horse collar did not restrict breathing and enabled horses to use the same strength of oxen. Also, horses had better endurance and faster speed. A free holder's house was wood, perhaps with a stone foundation, and roofed with thatch or tiles. There was a main room or hall, with bed chambers around it. Beyond was the kitchen, perhaps outside under a lean-to. These buildings were surrounded by a bank or stiff hedge.