If we turn to a comparison based upon taxation we have equal difficulties, though difficulties of a different sort.  We saw in the case of Old Windsor that a community of perhaps 1000, probably of more, but at any rate something more like a large village than a town (and one moreover not rated as a town), paid in dues the equivalent of thirty loads of wheat.  Wallingford paid the equivalent of only twenty or twenty-two.  But on the other hand the total Farm of the Borough, the globular price at which the taxes could be reckoned upon to yield a profit, was equivalent to no less than 400 such loads.

Judged by the number of hagae we should have a Wallingford about five times the size of Old Windsor.  Judged by the taxable capacity we should have an Old Wallingford of more than ten times the size of Old Windsor.

Here again a further element of complexity enters.  It was quite out of the spirit of the Middle Ages to estimate dues, whether to a feudal superior or to the National Government, or even minor payments made to a true proprietorial owner at the full capacity of the economic unit concerned.  All such payment was customary.  Even where, in the later Middle Ages, a man indubitably owned (in our modern sense of the word “owned”) a piece of freehold land, and let it (in our modern sense of the word “let"), it would not have occurred to him or his tenant that the very highest price obtainable for the productive capacity of the land should be paid.  The philosophy permeating the whole of society compelled the owner and the tenant, even in this extreme case, to a customary arrangement; for it was an arrangement intended to be permanent, to allow for wide fluctuations of value, and therefore to be necessarily a minimum.  If this was the case in the later Middle Ages where undoubted proprietary right was concerned, still more was it the case in the early Middle Ages with the customary feudal dues; these varied infinitely from place to place, rising in scale from those of privileged communities wholly exempt to those of places such as we believe Old Windsor to have been, which paid (and these were the exceptions), not indeed every penny that they could pay (as they would now have to pay a modern landlord), but half, or perhaps more than half, such a rent.

Where Wallingford stood in this scale it is quite impossible to say, and we can only conclude with the very general statement that the Wallingford of the Conquest consisted of certainly more than 5000 souls, more probably of 10,000, and quite possibly of more than 10,000.

Having taken Wallingford with its minute and valuable record as a sort of unit, we can roughly compare it with other centres of populations upon the river at the same date.