At what point in the story does it first seem that leiningen has snatched victory from the very jaws of defeat?

In the story "Leiningen Versus the Ants," it first seems that Leiningen has snatched victory from the jaws of defeat when he successfully channels the river to create a moat around his plantation. This strategic move appears to give him the upper hand against the relentless army of ants, as it momentarily halts their advance and allows him to regroup and devise further plans to combat the infestation. However, this moment of triumph is quickly overshadowed by the ants' relentless determination and the challenges that follow.