Pedantic military dispatches from the Nubian front, the Semna Dispatches, offer evidence of the existence of border patrols. These dispatches are a set of hieratic communiques between fortresses in Nubia, probably sent in the regnal year 3 of Amenemhat III (1853 Be). Since these documents came to rest in a Theban tomb, they presumably record messages sent to the official military headquarters established at Thebes, although no designation is specified in the texts themselves. The messages deal with the close military surveillance of the regions around the military installations, as in the case of one communication sent from a certain Ameny stationed at the Serra East fortress, some 25 kilometres north of Buhen, to a commander in the Theban administration: It is a communication to the Master, may he live prosper and be healthy, to the effect that the soldier of Nekhen ... came to report this to your servant at breakfast time on the second day of the fourth month of spring, in the third year, on a mission from the chief of the leaders of the town militia, Khusobek's son Mentuhotep's son, Khusobek ... who is acting in lieu of the leader of the crew of the ruler in the garrison of Meha [a district of Nubia], saying: 'The patrol that went out to patrol the desert-edge near the fortress of Khesef-Medjau [Serra East] on the last day of the third month of spring in the third year has returned to report to me, saying: We have found the track of thirty-two men and three donkeys ... ' (British Museum EA 10752.4) Two principal elements of Middle Kingdom military organization are readily apparent in this letter, namely the transference to the army of the Egyptian bureaucrats' precise attention to detail and the existence of a complex chain of command from overall commander down to common soldier. The overriding concern of all the dispatches lies in checks on all population movement within the section of the Nile valley in Nubia controlled by the Egyptians. Patrols watched for and reported any tracks left by valley or desert inhabitants of the area (denoted respectively as nhsyw 'Nubians' and md3yw 'Medjay'). The area between the First and Second cataracts seems to have been maintained by the Egyptians as a depopulated and militarized zone in the late Middle Kingdom. Punitive raids
There is no evidence that any of the fortresses in Nubia actually came under attack, and in fact they could have easily have been by-passed in the desert by anyone seriously intent on invading Egypt. If the Nubians had attacked them they would probably have proved nigh on impregnable, but the garrisons seem to have served their purpose as a deterrent and were not put to the ultimate test. I have already mentioned the armed 'march about', and the fortresses would have been used as bases for a short-term chevauchee by the Egyptians at times when the permanent garrisons were strengthened by the peasant conscripts belonging to the town militias. These late summer raids were sufficient to subdue any rebelliousness in the area, or at least prove who was in control.