Just at this time the exchange of P.O.W. to Holland began to operate. To some of the original conspirators, disheartened—and no wonder—at the apparent complete frustration of all their plans, the chance of going to Holland seemed too good to be given up for the now very distant hope of escape, and so it came about that the “ownership” of the tunnel changed hands almost completely, only three of the original conspirators remaining in the firm. As all doors were locked just before dusk, the available time was necessarily limited to daylight, between nine o’clock roll-call in the morning and evening roll-call about an hour before dark. The actual working hours were considerably shorter. In the first place, the coast was never sufficiently clear in the morning for the tunnel to be approached until about 11.30 a.m., and in the second place, a considerable margin had to be allowed, when coming off duty, for any possible delay in getting a clear exit and so running the risk of being discovered absent from _appel_. In addition to this, the time spent in changing clothes had to be taken into account. Consequently the actual working hours were not, as a rule, longer—in winter—than from 12 noon to 4 p.m. This arrangement, however acceptable to a trades union official, was not good for tunnelling. As will be understood, the utmost care had to be exercised in approaching the orderlies’ entrance in order to gain access to the tunnel, and the ordinary daily programme was carried out on something like the following lines. We will assume that it is about 11 a.m.