Mewling and puking

There was a time, not all that long ago, when it was virtually impossible to procure a high-school diploma without having learned to recite from memory the "seven ages of man" speech by Jacques in As You Like It. In one of the two mysteries by Michael Dibdin borrowed from the library for evening reading and polished off this week, "mewling" appeared as "muling." The author put it there and copy-editors and proof-readers left it there.