Ater

ATER or NIGER MONS, a mountain range of Inner Libya, on the N. side of the Great Desert ( Sahara), dividing the part of Roman Africa on the Great Syrtis from Phazania ( Fezzan). It seems to correspond either to the Jebel-Soudanor Black Mount(ins, between 28° and 29° N. lat., and from about 10° E. long. eastward, or to the SE. prolongation of the same chain, called the Black Harusch, or both. The entire range is of a black basaltic rock, whence the ancient and modern names (Plin. Nat. 5.5, 6.30. s. 35; Hornemann, Reisen von Kairo nach Fezzan, p. 60).
[P.S]