He says they navigate and move toys around by bursts of air. I'm pretty sure he means water. Otherwise they would have to be making trips to the surface to get refills.

Do they have editors at Slate?

He means water. Actually he says it twice, about modern octopus and about the earliest cephalopods. From Discover magazine: "Mather describes several ways octopuses use their water jet as tools: to clean their dens, push away rocks and other debris, and drive off pesky scavenger fish."

This and the "half a million neurons" are pretty obvious errors that are a bit disappointing from Zimmer, who generally is a very good popular science writer.