The wards in London most probably represented the groups of citizens belonging to several gilds; they may indeed be identical with the Peace gilds of Athelstane's enactment, according to which the population were to be enrolled by tens and hundreds in associations for the preservation of peace and the suppression of theft.[146] In accordance with this idea of accounting for every man, we find that even in the thirteenth century no one was to stay in the city for more than two nights "unless he finds two sureties and so puts himself in frankpledge." The aldermen were responsible for their wards,[147] and every hosteller was likewise responsible for his guest.[148] Dr. Maitland suggests that the Aldermen were the military captains of the burgmen. It is certain that the defence of the town gates was assigned to the men of the several wards. The wards, then, were in the main organisations for the executive government, the ordering and policing of the city. "The ward-mote is so called as being the meeting together of all the inhabitants of a ward in presence of its head, the alderman, or else his deputy, for the correction of defaults, the removal of nuisances, and the promotion of the well-being of each ward."[149] This function, indeed, is explained by the very name "ward," and the "frankpledge" was a survival of primitive adoption into the tribe. Some recognition of this is made by Holinshed, who says the city is divided into twenty-six wards or "tribes." It even seems possible that the wards may at first have been formed by symmetrical numerical units such as, say, a hundred freemen; or the space within the walls may have been divided up into twenty or twenty-four parts in such a way as to allow for density of population. Excavations in the city have shown that the population clustered most thickly along the river and in the great streets, and the wards are much more congested and regular in the central part by the bridge than nearer the walls: the old churches also seem to gravitate towards the same nucleus. _Wards without._--A good illustration of the formation of the interior wards may be found in the growth of those without the walls. Bishopsgate Without, and Aldersgate Without, were evidently formed by clusters of dwellings springing up on either side of the roads outside the gates. Cottages outside Bishopsgate and at Holborn are mentioned even in Domesday, and Fleet Street appears to have been populous even earlier. The external wards extend to the boundary of the city liberties, or common land, and the roads passing through them had specific street-names as far as the several "Bars." Holborn Street, as it is sometimes called, which passed over the Hole-burn, should properly end with the city liberty, as does Fleet Street.