more than collections of anchorites were liable to the decay consequent upon the rivalry of their inmates. St Benedict enjoined emulation in good works among his monks; but their emulation had its root in humility and obedience, and its outward sign was a mutual deference far removed from spiritual pride. There can be little wonder that a rule, difficult but possible to follow, and allowing for individual weakness, spread far outside the community for which it was made, and that the Benedictine order by the end of the seventh century supplanted all other forms of monasticism in western Europe. § 5. The rule of St Benedict was introduced into England by St Augustine, prior of the monastery on the Coelian hill in Rome. At this time the chief strength of Celtic monachism was naturally in the north, although it had penetrated southwards to such isolated outposts as Glastonbury. Gradually Roman customs gained ground in the strongholds of Celtic Christianity. The grant of the monastery of Ripon to Wilfrid was followed by the departure of the Scottish monks. Little is definitely known of English monastic life at this period, but it is clear that it began to approximate more closely to the Benedictine model. Thus the nuns of Hackness, an offshoot of the monastery of Whitby, had a common dormitory; while the monasteries of Monkwearmouth and Jarrow differed in many respects from the local pattern, and were certainly established upon a principle of common life. In certain features a compromise seems to have been arrived at, as in the survival of the custom, which had probably been introduced by Irish missionaries, of grouping monks and nuns in one monastery under the presidency of an abbess. The most famous instance of this was the abbey of Whitby, but other examples are known in various parts of England remote from each other. For a few of these models may have been found in Gaul, where the Benedictine rule was not introduced until a period later than the coming of Augustine. Another feature was the establishment of bishops' sees in monasteries. In European countries where the traditions of the Roman occupation were more or less continuous, the cathedral within the city was a distinct foundation from the monasteries which, as at Paris or Rouen, rose at a later date outside the walls. But the Celtic missionaries in England broke new ground in a country from which the traces of Roman Christianity had almost disappeared, and their sees were founded in monasteries. This custom was followed in the natural order of things by Augustine at Canterbury. In the reorganisation of dioceses after the Norman conquest it was still continued. In eight of the seventeen medieval dioceses of England the cathedral, and in two others one of the two cathedrals, was a monastic church.