An open door on my right showed me a small room, absolutely empty, except for a row of tins against the wall. Knowing that petrol was carried in such tin drums I went and examined them. The next moment Allan heard a shout that brought him hastily inside, wondering whether I had gone mad, had been bitten by a wild beast, or was being murdered. "Look!" I cried, as he came running up to me. "Look at those tins and tell me what's inside!" Allan seized hold of one of the drums, read what was written on it, gave it a shake, and we could both hear the blessed sound of lapping inside. "It's petrol, sir," he whispered in an awed voice. Petrol in the desert--petrol where one would as soon have expected to find a Bond Street jeweller! At first we could neither of us believe it. Personally I imagined we had both got temporary jim-jams, but Allan, with his usual stolid, common sense, opened one of the drums, tested the contents, and pronounced it to be first-class petrol. There were seven drums, each containing four gallons. "This means we'll motor, not walk into Robat after all, sir," said Allan, with a grin and sigh of relief. The thought of those miles of desert--nearly two hundred of them--which confronted us after the mishap had been haunting us both like a nightmare. At this moment the _chokidar_ returned, in great trepidation, fearing a dressing-down for being absent from duty. But I was far too elated at the turn of events to want to swear at anyone. I asked him where the petrol had come from, and whose it was. He shook his head, and said he had no idea. It had always been there. It belonged to no one, and no one had put it there, so far as he knew. He had never seen a car there before; in fact, he had never seen a car anywhere before, and could not understand how it was that men could travel on a thing which was not alive, which was not like any horse or camel he had ever seen. This was all very good hearing, so I proceeded to tell him that the petrol belonged to me, and, as he quite cheerfully acquiesced, I gave him a receipt which he could show to any Government official in case of needed absolution in the future. As we now had means to finish our journey by car, I decided to spend the night at the rest-house. After a simple camp meal Allan, worn out with the strenuous work of the past two days and night, was quickly snoring in the deep sleep of exhaustion, so I went for a stroll.