Noname's copy editor took this issue off:

As the story opens, Frank gets a cable from Paris. Imagine that! It's from the government,which has formed a company to irrigate the Egyptian desert - that being the sort of technological and benevolent thing the French were known for doing. Smart as they were, though, they lacked Frank's submarining skill, and needed him to explore an underground river.

He breaks the news to his employees, who react in the customary manner:

What's interesting about this one is the way Frank trashes his vessel:

A storm moves hte sub to the desert. For one he seems to have chosen the wrong tool for the job.