During the course of a railway survey, carried over the high plateaus of Haurân and Jaulân, I found occasion to extend my researches into the neighbouring Kada of Irbid, the country sometimes called ʾAjlûn, which includes part of the Biblical district of the Decapolis or Ten Cities. This district lies on the south or left bank of the Yarmûk, which river formed the southern limits of the Map which accompanied the Memoir published in 1886 under the title of “Across the Jordan.” During my journeys through ʾAjlûn, special attention was directed to the Wâd el-ʾArab and its tributaries, for it was originally my intention to have extended the surveys eastwards as far as the Wad esh-Shelâleh. I found, however, that this country was so intersected with ravines and wâdies, covered by a thick growth of oak forest, as to render its survey extremely laborious, and the time at my disposal being limited, I was forced to abandon my task, after having mapped and examined only a portion of this interesting country. The sites of Umm Keis, the ancient Gadara, and Beit Râs, the supposed representative of Capitolias, had not hitherto been as thoroughly explored as their importance seemed to merit, and I therefore spent nearly two weeks of my time amidst their ruins, in order to make the detailed plans and sketches which will be found in the following Memoir.