Meanings of rival editors in English

Though rival editors facing our way, they had not been admitted to the Quadrilateral.

They therefore follow the safer example of rival editors, and swear and scold at each other.

His own amusing account of the rival editors in Pickwick might have instructed him on this latter point.

What is going to happen to the mental processes of the rival editors, each of whom must now mistrust all her ideas?

And I am extremely indebted to Jeaniene Frost for hours of talking, revision letters to rival editors' letters, and so many epiphany-stirring observations.