Here they have levelled the trees and stamped the earth flat, so that they may gambol and chase one another, and the calves may fight to the applause of trumpetings and waving trunks. There are many rotting huts in the Wood of the Waters, for the Isisi send here the old, the blind, and the mad, that they may die without distressing the whole and the sane. Sometimes they kill one another, but generally a scaly form creeps up from the mud and knocks them into the water with its quick tail, and there is an end.

Mr Commissioner Sanders was mad, but not slayable, by reason of his soldiers, his long-nosed “wung-wung” (so they called his hotchkiss) and the brass-jacketted guns that said “ha-ha-ha!”

Nobody but a madman would go squelching through the noisome mud of the wood, peering into foul huts, raking over ground for signs of skeletons (all that the crocodiles did not take was the little red ants’ by right). Yet this is what Sandi did. He slowed his fine boat and brought her to the bank.

“I have impressed upon Lulaga the impropriety of hastening the deaths of his relatives,” he said to Captain Hamilton of the Houssas, “and he has sworn by M’shimba and his own particular devil that there shall be no more blinding or old-age pensioning,” he added grimly.

Hamilton smiled wearily. “‘The customs of the country must not be lightly overridden or checked,’” he quoted from a famous Instruction received from the Colonial Office in bygone days – there isn’t a Commissioner from K’sala to Tuli Drift who cannot recite it by heart, especially after dinner.

“‘Nor,’” he went on, “‘should his religious observances or immemorial practices be too rudely suppressed, remembering that the native, under God’s providence, is a man and a brother.’”

“Shut up!” snarled Sanders, but the inexorable Houssa was not to be suppressed.

“‘He should be approached gently,’” he went on, “‘with arguments and illustrations obvious to his simple mind. Corporal punishment must under no circumstances be inflicted save in exceptionally serious crimes, and then only by order of the supreme judiciary of the country – ’”

“That looks to me like a new hut,” said Sanders, and stepped over the hastily rigged gangway, twirling a mahogany stick in his thin, brown hand.

Threading his way through a green and anaemic plantation, he came to the hut, and there he found B’saba, sometime headman of the village of M’fusu, and B’saba was mad and silly and was chuckling and whimpering alternately, being far gone in sleeping sickness, which turns men into beasts. He was blind, and he had not been blind very long.

The nose of Sandi elaka wrinkled.

“O man, I see you, but you cannot see me. I am Sandi, who gives justice. Now tell me, who brought you here?”

“Lulaga the king,” said the old man woefully. “Also he has taken my pretty eyes.”

He died that night, Sanders squatting on the ground by his side and feeding the fire that warmed him. And they buried him deep, and Sanders spoke well of him, for he had been a faithful servant of Government for many years.

In the dawn-grey he turned the nose of the Zaire against the push of the black waters and came to the village of the chief, to that man’s uneasiness.

The lokalis beat a summons to a great palaver, and in the reed-roofed hut Sanders sat in judgment.

“Lord!” said the trembling Lulaga. “I did this because of a woman of mine who was mocked by the old man in his madness.”

“Let her come here,” said Sanders, and they brought her, a mature woman of sixteen, very slim, supple and defiant.

“Give me your medal, Lulaga,” said Sanders, and the chief lifted the cord that held his silver medal of chieftainship. And when Sanders had placed it upon the neck of a trustworthy man, and this man had eaten salt from the palm of the Commissioner’s hand, soldiers tied Lulaga to a tree, and one whipped him twenty times across the shoulders, and the whip had nine tails, and each was a yard in length.

“Old men and madmen shall die in good time,” said Sanders. “This is the law of my King, and if this law be broken I will come with a rope. Hear me! The palaver is finished.”

There came to him, as he made his way back to the ship, an elderly man who, by the peculiar shape of his spear, he knew was from the inner lands.

“Lord, I am M’kema of the village by the Frenchi,” he said, “being a chief of those parts. Now, it seems to me that you have taken away the magic which our fathers gave to us, for all men know that the sick and old are nests where devils breed, and unless we kill them gently there will be sickness in the land. On the other side of the little river the Frenchi people are very sick, and some say that the sickness will come to us. What magic do you give us?”

Sanders was instantly alert.

“Any men of the Frenchi tribes who cross the river you shall drive back with your spears,” he said, “and if they will not go, you shall kill them and burn their bodies. And I will send Tibbetti, who carries many wonders in a little box, so that you shall not be harmed.”

On the way down river, Sanders was unusually thoughtful. Not less so was Captain Hamilton, for, as the elder man had said, from the beginning of time every tribe, save the Ochori, had carried its ancient men and women into the forest and left them there to die. Sanders had threatened; he had on occasions caught men in the act of carrying off their uncomfortable relatives; but never before had he punished so definitely for a custom which the ages had sanctioned.

They smelt headquarters before they saw the grey quay and the flowering palm-tops that hid the residency. Suddenly Sanders sniffed.

“What in the name of Heaven – !” he asked.

A gentle wind, blowing in from the sea, carried to him a strange and penetrating odour. It was not exactly the smell of tar, nor was it the scent which one associates with a burning soap factory. It combined the pungent qualities of both. Later, Sanders learnt that, in his absence, a trading steamer had called and had landed half-a-dozen carboys of creosote for the use of the Health Officer, and that Bones, in his enthusiasm and in that capacity, had tried the experiment of a general fumigation. The fire whereon the creosote had been transformed into its natural gases, still smouldered in the centre of the square, and Bones, a fearsome object in a gas mask, and without any assistance – his men had practically mutinied and flown to their huts – was continuing the experiment when, in sheer self-defence, Sanders pulled the siren of the Zaire and emitted so blood-curdling a yell that it reached beyond the protective covering of Bones’ mask.

“For the love of Mike, what are you trying to do?” gasped Hamilton, spluttering and coughing.

Bones made signs. After his helmet had been removed, he propounded the results of his experiments.

“There isn’t a jolly old rat left alive,” he said triumphantly; “the beetles have turned in their jolly old numbers, and the mosquitos have quietly passed away!”

“Are any of the company left?” demanded Hamilton. “Phew!”

“Creosote,” began Bones, in his professorial manner, “is one of those jolly old bug-haters–”

“Bones, I’ve got a job for you,” said Sanders hastily. “Get steam in the Wiggle and go up to the Lesser Isisi and on to the French frontier.