The next four days, though they were days of waiting, were busy enough to satisfy the most impatient Mayoruna warrior. Outposts were established on every route by which the attacking force would be likely to approach the twin _malocas_, the watchmen being given the strictest commands not to fight, nor even to allow themselves to be seen, but to run at top speed with the warning. Poison detachments went forth to collect the ingredients for making deadly the water and the weapons. Those detailed to the work of polluting the streams gathered quantities of blue-blossomed, short-podded plants with yellow roots, the roots being pulped and thrown into the slow currents, which straightway became fatal to man or beast The wurali squad procured their favorite materials and, in a flimsy shed well away from the houses, prepared a plentiful supply of the venomed brew. New traps were set at points where a man or two might be picked off, though it was realized that these would have little effect on the final result. And inside the big houses men especially skilled in the manufacture of arrows and darts toiled swiftly and steadily from dawn till far into the night. These activities, however, were only the usual defensive preparations made by the warriors whenever they knew a sizable body of foes was somewhere in the vicinity. It remained for the brains of the white men to devise additional features, simple enough in themselves, but astounding to the savages, who were accustomed only to the primitive battle tactics of their ancestors. For the first time in their lives the cannibals found themselves digging in--and also digging out. After a survey of the terrain and a catechism of Lourenço and Monitaya as to the usual methods of attack and defense, the two officers broached an idea born of the exigencies of the situation. As they expected, the great chief was somewhat slow to approve it, for it involved a literal undermining of the walls of his fortresses. But despite the natural inflexibility of his mental processes he was an unusually intelligent savage, and eventually the patient reiteration of the advantages of the scheme won him first to assent and then almost to enthusiasm. Wherefore the amazed tribesmen were set to work, armed with crude wooden shovels, in digging holes under the logs which sheltered them from man, beast, and jungle demon.