Enlarge on the author's reference to Romulus and Remus and the firsé low wall around the city of Rome.

From the text:

I thought of the story we read in the old his- tories of Rome, of how Remus jumped scornfully over the first low wall of the city. Romulus killed him, and I expect Sir Philip would cheerfully have killed Dick Hudson if he'd seen him at that moment. But Sir Philip wasn't there, and he'd never know. . . . When people asked who'd overthrown that wall, we were all going to say it must be the work of the devil, The devil has a great reputation for destroying what honest men would be glad to see out of the way !