fact that the Norman gentry, in their greed for gain, were by no means above indulging in speculations of the kind. But when we make the interesting discovery that William de Eynsford, in this same reign, had acted as Sheriff of London,[1042] may we not infer that, there also, he had indulged in a similar speculation? That the shrievalty of London (_i.e._ London and Middlesex) was purchased by payments "de gersoma" is a matter, itself, not of inference, but of fact. Fulcred fitz Walter is debited in the Pipe-Rolls with a sum of "cxx marcas argenti de Gersoma pro Vicecomitatu Londoniæ."[1043] The _firmarius_ who had succeeded in obtaining a lease would have to recoup himself, of course, from his receipts the amount of the actual "firma" _plus_ his payment "de gersoma," before he could derive for himself any profit whatever from the transaction. This implied that he had closely to shear the flock committed to his charge. If he was a mere speculator, unconnected with his sphere of operations, he would have no scruple in doing this, and would resort to every means of extortion. What those means were it is now difficult to tell, for, obscure as the financial system of the Norman period may be, it is clear that just as the _rotulus exactorius_ recorded the amounts to which the king was entitled from the _firmarii_ of the various counties, so these _firmarii_, in their turn, were entitled to sums of ostensibly fixed amount from the various constituents of their counties' "corpora." Domesday, however, while recording these sums, shows us, in many remarkable cases, a larger "redditus" being paid than that which was strictly due. The fact is that we are, and must be, to a great extent, in the dark as to the fixity of these ostensibly stereotyped payments. That the remarkable rise in the annual _firmæ_ exacted from the towns which, Domesday shows us, had taken place since, and consequent on, the Conquest would seem to imply that these _firmæ_, under the loose _régime_ of the old system, had been allowed to remain so long unaltered that they had become antiquated and unduly low. In any case the Conqueror raised them sharply, probably according to his estimate of the financial capacity of the town. And this step would, of course, involve a rise in the total of the _firma_ exacted from the _corpus comitatus_. The precedent which his father had thus set was probably followed by Henry I., who appears to have exacted, systematically, the uttermost farthing. It was probably, however, to the oppressive use of the "placita" included in the "firma comitatus" that the sheriffs mainly trusted to increase their receipts.