But whatever may have been the means of extortion possessed by the sheriffs in the towns within their rule,[1044] and exercised by them to recoup themselves for the increased demands of the Crown, we know that such means there must have been, or it would not have been worth the while of the towns to offer considerable sums for the privilege of paying their _firmæ_ to the Crown directly, instead of through the sheriffs.[1045] I would now institute a comparison between the cases of Lincoln and of London. In both cases the city formed part of the _corpus comitatus_; in both, therefore, its _firma_ was included in the total ferm of the shire. Lincoln was at this time one of the largest and wealthiest towns in the country. Its citizens evidently had reason to complain of the exactions of the sheriff of the shire. London, we infer, was in the same plight. Both cities were, accordingly, anxious to exclude the financial intervention of the sheriff between themselves and the Crown. How was this end to be attained? It was attained in two different ways varying with the circumstances of the two cases. London was considerably larger than Lincoln, and Middlesex infinitely smaller than Lincolnshire. Thus while the _firma_ of Lincoln represented less than a fifth of the ferm of the shire,[1046] that of London would, of course, constitute the bulk of the ferm of Middlesex. Lincoln, therefore, would only seek to sever itself financially from the shire; London, on the contrary, would endeavour to exclude, still more effectually, the sheriff, by itself boldly stepping into the sheriff's shoes. The action of the citizens of Lincoln is revealed to us by the Roll of 1130:— "Burgenses Lincolie reddunt compotum de cc marcis argenti et iiij marcis auri ut teneant ciuitatem de Rege in capite" (p. 114). The same Roll is witness to that of the citizens of London:— "Homines Londonie reddunt compotum de c marcis argenti ut habeant Vic[ecomitem?] ad electionem suam" (p. 148).