Unless the ants know how to build rafts, they won't reach the plantation.
6 seconds sound clip from the Leiningen Versus the Ants (1948) classic radio play.
You can hear this line at 00:08:47 in the radio play.
Quote context
[...]
- For, as we now approached the ditch and rode along it, I could see that it was nearly full.
- How do you like my first line of defense, Commissioner?
- It's... reassuring, like a moat around a castle.
- Unless the ants know how to build rafts, they won't reach the plantation.
- This is only the outer moat. There's a better one than this.
- I didn't see any women or children around the plantation, or any animals.
- Yes, that's right. Moved them across the river.
- Then even you think there is danger?
- Not because of danger. A matter of efficiency.
[...]