Since that experience I have made it an invariable rule in my travels to cut a small clearing before putting up my tent in the jungle. Sometimes the felling of one or two trees will ameliorate the situation immeasurably, admitting fresh air and sunlight, and there is little difficulty about it when one is accompanied by such able and willing men as the Dayaks. For their own use when travelling they make simple shelters as night approaches, because they dislike to get wet. The material is always close at hand. Slender straight poles are quickly cut and brought in to make frame-work for a shed, the floor of which is about half a metre above ground. The roof is made of big leaves, and in less than an hour they are comfortably at home in one or more sheds, grouped around fires on the flimsy floor. It is a curious fact that one can always manage to make a fire in these damp woods; a petroleum burner is not essential. The natives always know where to go to find something dry that will burn; as for the white man's cook, he usually improves upon the situation by soaking the wood in petroleum, which is one of the valuable articles of equipment. Often in the jungle, when slightly preparing the ground for erecting the tent, phosphorescent lights from decayed vegetable matter shone in innumerable spots, as if a powerful lamp were throwing its light through a grating. In ascending the hills it was surprising how soon the aspect of the vegetation changed. The camp we were just leaving was only about a metre above the Kayan River, so we probably were not more than twenty-odd metres above sea-level. Twenty metres more, and the jungle vegetation was thinner even at that short distance. Trees, some of them magnificent specimens of hard wood, began to assert themselves. Above 100 metres elevation it was not at all difficult to make one's way through the jungle, even if we had not had a slight Punan path to follow. It is easier than to ascend the coast range of northeast Queensland under 18° S.L., where the lawyer palms are very troublesome. Making a light clearing one evening we opened the view to a couple of tall trees called in Malay, palapak, raising their crowns high above the rest; this is one of the trees from which the natives make their boats. The trunk is very tall and much thicker near the ground. Reaching a height of 500 metres, the ground began to be slippery with yellow mud, but the jungle impeded one less than the thickets around Lenox, Massachusetts, in the United States. Toward the south of our camp here, the hill had an incline of 45 degrees or less, and one hardwood tree that we felled travelled downward for a distance of 150 metres. A pleasant soft breeze blew for about ten minutes, for the first time on our journey, and the afternoon was wonderfully cool.