In medieval times in England, the lord of a manor, when leasing farms to tenants, reserved the right to let his pigeons forage over them. As pigeons live mostly upon grains and seeds, caring little for green vegetation and insects, the newly planted fields of the farmer were the favorite feeding places of his landlord's pigeons. The landlords, being able to keep pigeons without other expense than that of providing shelter for them, built large dovecots near the manor houses and kept their tables plentifully supplied with pigeons. At one time it was estimated that there were more than twenty thousand such dovecots in England. The destruction of crops by the occupants of these caused serious losses to the farmers and a great deal of trouble between them and their landlords. This form of protection for roving pigeons in agricultural districts was finally abandoned. No doubt the selfishness of landlords was originally responsible for this method of protecting pigeons, but the government of the country at that time also had something to do with it. Pigeon manure is very rich in niter, which in those days the government had difficulty in procuring in such quantities as it needed for the manufacture of gunpowder; so it adopted the policy of regulating the construction of pigeon houses, prescribing the method of disposing of the droppings to conserve the niter in them and appointing official inspectors to see that its regulations were observed, and collectors to gather the pigeon manure. It was much easier to do this when large flocks were kept by landlords than when an equal number of the birds were kept in small flocks by the tenants. =Place in domestication.= Although many farmers keep small flocks of pigeons, the pigeon in modern times is a city bird rather than a country bird. The strong flying types are all well adapted to an independent life in towns and cities, where, as has been stated, they often become a nuisance. This form of nuisance might be partly abated and perhaps prevented if city authorities would systematically and humanely exterminate the free flocks of common pigeons, and encourage citizens to breed improved varieties under proper control.