I was more than sorry to lose his cheery company, and toiled on through the terrible loneliness of the dunes, feeling rather down in the mouth. I had about six hours’ walk before me, and knew the route, and there was no hurry, so, finding a few t’samma, I sat down and ate some and chewed a bit of biltong. Now, for a long time I had been on the lookout for a variety of “truffle” which grows in the Kalahari after rain, and which not only the Bushmen eat, but which white people esteem a great delicacy. It is called by the Bushmen name _naba_, and though I had never seen it, I had often had it described to me. It does not appear above ground at all, but is detected by a slight swelling and cracking of the soil under which it is growing. Enthusiastic friends had told me that it was not only a true truffle, but that it knocked spots off anything ever produced in Perigord. Well, as I sat in the dunes munching t’samma and biltong of the consistency of an old boot, and thinking of all the nice things I would have when once I got into a town again, I noticed that the earth quite close to me had several of these little, gentle swellings, and, scraping away the sand, I found about half a dozen little fungi about the size of a small potato--which could be nothing but _naba_. I had no means of cooking them then, and put them in my haversack, resolving to test them the moment I reached a frying-pan. However, about an hour later, still trudging along, I took one out to have a better look at it. It certainly smelt nice, just like a young, fresh button mushroom. Perhaps it would be nice raw? I nibbled a bit--it was! So I ate it, and two others followed.... I got no farther, for quite suddenly the dunes began to spin round, a deadly nausea seized me, and I realised that I had been poisoned. There was nothing to be done--I could not even find a t’samma to eat, and within a few yards the Kalahari seemed to get up and smite me violently, and down I went, the whole universe swaying round me in a most unpleasant manner. However, after about an hour of excitement I got the better of it, and was able to walk again, though I felt like a chewed rag, and did not get out of the desert and into the old Molopo till well after dark. I have tasted _naba_ since then, and enjoyed it--but cooked!