Just for fun -

Once a molicepan met a bittle lum Sitting on the sturbcone eating gubber rum Mmmm said the molicepan, simme gum Not on a sam dight said the bittle lum

Growing up in the 1930s, mom said the was the girls favorite pastime - swapping letters of different phrases.

I know you were looking for more serious things, but this was fun for me to memorize years ago and try to put into play with other phrases.