As chief executor of the archon’s sentences, I was required to attend these sessions, so that he might be assured that the punishments he decreed should be made neither softer nor more severe by those who might otherwise have been charged with transmitting them to me; and to oversee the operation of the Vincula, in which the prisoners were detained, in all its details. It was a responsibility equivalent on a lesser scale to that of Master Gurloes in our Citadel, and during the first few weeks I spent in Thrax it weighed heavily upon me.

It was a maxim of Master Gurloes’s that no prison is ideally situated. Like most of the wise tags put forward for the edification of young men, it was inarguable and unhelpful. All escapes fall into three categories — that is, they are achieved by stealth, by violence, or by the treachery of those set as guards. A remote place does most to render escapes by stealth difficult, and for that reason has been favored by the majority of those who have thought long upon the subject.

Unfortunately, deserts, mountaintops, and lone isles offer the most fertile fields for violent escape — if they are besieged by the prisoners’ friends, it is difficult to learn of the fact before it is too late, and next to impossible to reinforce their garrisons; and similarly, if the prisoners rise in rebellion, it is highly unlikely that troops can be rushed to the spot before the issue is decided.

A facility in a well-populated and well-defended district avoids these difficulties, but incurs even more severe ones. In such places a prisoner needs, not a thousand friends, but one or two; and these need not be fighting men — a scrubwoman and a street vendor will do, if they possess intelligence and resolution. Furthermore, once the prisoner has escaped the walls, he mingles immediately with the faceless mob, so that his reapprehension is not a matter for huntsmen and dogs but for agents and informers.