It is an "OLD, OLD" tool used in the days before Secure Internet Security and PGP's encryption.

Read each word as it poetic (stressed/nonstress) (Iambic, Trochi, etc) equivilant.....and convert into Morse Code....

EXAMPLE:
dour = one-long = T
embraceable=four-short = H
benchmark = two-short + I
mayflower = three-short = S

i.e. THIS

lyric = long-short = N

etc. etc.

Sincerely,
Gargoyle