Why are gasoline pipes an important part of the defense against the ants in "Leiningen Versus the Ants"?
The gasoline pipes are essential to defense against the ants because with a "rampart of petrol" the men can protect the inner ditch that surrounds the hill on which stand the manor house, barns, stables, and outbuildings.
While the other plantation owners have conceded defeat, Leiningen is convinced that the human brain can conquer the elements. Against the advice of the District Commissioner, he and his loyal men do not abandon the plantation to the onslaught of a plague of ants. First, the three-sided moat around the property is filled with water (the fourth side is the river) in order to prevent the ants' passage. However, the ants are in biblical numbers, and they start to cross. Leiningen orders the water lowered, then flooded; still, the flow of the water is not strong enough to keep pace with the forward-marching ants. Therefore, Leiningen orders the men to grab the petrol sprinklers that are used to destroy pests and blight. When the ants are sprayed, they respond with an ever-widening front in order to make their crossings.
The ants collect shreds of bark, twigs, and dried leaves along with the tamarind leaves used as rafts before.
Leiningen and his men find retreat necessary, so they pull back to the inside of the moat into which the gasoline can pour. There they set fire to hoards of ants that come one after another, but this defense eventually fails because the pumps malfunction. Now Leiningen begins to worry; he suddenly remembers that an outhouse nearby has two old, unused fire engines inside it. After the peons pull these engines out and connect them to the cisterns, the war is re-engaged. However, this is only a temporary victory. The ants begin to build bridges, so Leiningen must create a new plan. He decides that if he can flood the plantation—the house and other buildings are on high ground—his most valuable property can be saved. But almost two miles lie between the weir on the river, so Leiningen will have to make the run himself because he cannot ask any of the men to do it. Soon, covered with gasoline and an Indian salve whose odor repels ants, along with his tight mosquito goggles, Leiningen begins his run. Before departing he has instructed his men,
"The moment I'm over the ditch, set fire to the petrol. That'll allow time for the flood to do the trick. Then all you have to do is wait here all snug and quiet till I'm back. Yes, I'm coming back, trust me...."
After running the gauntlet of ants who invade his clothes and even his goggles, Leiningen makes it to the weir and lowers it until the water overflows the ditch. In another minute the water is flooding the plantation. Covered with ants and in agony, Leiningen runs back. The men rush to knock off as many ants as they can; they rip away his clothes. Leningen has raw flesh exposed, some of which is gone to the bone. Fortunately, he survives, although he is "a bit streamlined."