[Illustration: FIG. 23. Ledjdjûn. (From _Provincia Arabia_, by kind permission of Professor Brünnow.)] The second or outer limes cannot be much later in date, and in all probability it belonged to the time which saw the fortification of the road from Palmyra to Damascus. Ḍumair (Plate 78, Fig. 2), the second of the chain of forts that extended from Damascus to the desert capital,[197] is dated by an inscription in the year A.D. 162; it bears a close resemblance both to Trajan’s camp at [Illustration: FIG. 24. Da’djaniyyeh. (From _Provincia Arabia_, by kind permission of Professor Brünnow.)] Odhruḥ and to Ledjdjûn, a camp on the outer Arabian limes. The salient, rounded, intermediate towers and circular angle towers of Odhruḥ are repeated at Ḍumair with unimportant variations in detail. No part of the Praetorium is standing, but there are traces of some of the rows of huts in the Praetentura, and according to Domaszewski’s plan they extended, on one side at least, over the Intervallum to the wall.[198] In the Retentura one ruined building remains, which the learned archaeologist believes to have been the Armamentarium. In the camp of Ledjdjûn the walls and towers are an exact copy of those of Odhruḥ (Fig. 23). The interior buildings belong to two periods. The greater part of the Praetorium, and a small apsed structure to the north of it, belong to the first period; and to the same date, Domaszewski assigns certain buildings placed along the walls between the towers, the largest of which he takes to have been a Horreum. The rows of barracks which fill the eastern half and a part of the western half of the camp are of later date and belong probably to the time of Diocletian.