Quietly we regained our camels and slept. Next morning we returned on our tracks to let a fold of the plain hide us from the railway, and then marched south across the sandy flat; seeing tracks of gazelle, oryx and ostrich; with, in one spot, stale padmarks of leopard. We were making for the low hills bounding the far side, intending to blow up a train; for Zaal said that where these touched the railway was such a curve as we needed for mine-laying, and that the spurs commanding it would give us ambush and a field of fire for our machine-guns.
So we turned east in the southern ridges till within half a mile of the line. There the party halted in a thirty-foot valley, while a few of us walked down to the line, which bent a little eastward to avoid the point of higher ground under our feet. The point ended in a flat table fifty feet above the track, facing north across the valley.
The metals crossed the hollow on a high bank, pierced by a two-arched bridge for the passage of rainwater. This seemed an ideal spot to lay the charge. It was our first try at electric mining and we had no idea what would happen; but it stood to our reason that the job would be more sure with an arch under the explosive because, whatever the effect on the locomotive, the bridge would go, and the succeeding coaches be inevitably derailed.
The ledge would make an admirable position for Stokes. For the automatics, it was rather high; but the enfilade would be masterful whether the train was going up or down the line. So we determined to put up with the disadvantages of plunging fire. It was good to have my two British responsibilities in one place, safe from surprise and with an independent retreat into the rough: for today Stokes was in pain with dysentery. Probably the Mudowwara water had upset his stomach. So