The buaze-trees and bamboos are now seen on the hills; but the jujube or zisyphus, which has evidently been introduced from India, extends no further up the river. We had been eating this fruit, which, having somewhat the taste of apples, the Portuguese call Macaas, all the way from Tette; and here they were larger than usual, though immediately beyond they ceased to be found. No mango-tree either is to be met with beyond this point, because the Portuguese traders never established themselves anywhere beyond Zumbo. Tsetse flies are more numerous and troublesome than we have ever before found them. They accompany us on the march, often buzzing round our heads like a swarm of bees. They are very cunning, and when intending to bite, alight so gently that their presence is not perceived till they thrust in their lance-like proboscis. The bite is acute, but the pain is over in a moment; it is followed by a little of the disagreeable itching of the mosquito's bite. This fly invariably kills all domestic animals except goats and donkeys; man and the wild animals escape. We ourselves were severely bitten on this pass, and so were our donkeys, but neither suffered from any after effects. Water is scarce in the Mburuma pass, except during the rainy season. We however halted beside some fine springs in the bed of the now dry rivulet, Podebode, which is continued down to the end of the pass, and yields water at intervals in pools. Here we remained a couple of days in consequence of the severe illness of Dr. Kirk. He had several times been attacked by fever; and observed that when we were on the cool heights he was comfortable, but when we happened to descend from a high to a lower altitude, he felt chilly, though the temperature in the latter case was 25 degrees higher than it was above; he had been trying different medicines of reputed efficacy with a view to ascertain whether other combinations might not be superior to the preparation we generally used; in halting by this water he suddenly became blind, and unable to stand from faintness. The men, with great alacrity, prepared a grassy bed, on which we laid our companion, with the sad forebodings which only those who have tended the sick in a wild country can realize. We feared that in experimenting he had over-drugged himself; but we gave him a dose of our fever pills; on the third day he rode the one of the two donkeys that would allow itself to be mounted, and on the sixth he marched as well as any of us. This case is mentioned in order to illustrate what we have often observed, that moving the patient from place to place is most conducive to the cure; and the more pluck a man has--the less he gives in to the disease--the less likely he is to die.