TheCodeBreakers
without delay X Warn aviation of canoes crossing Ferguson RE. He drew
up a square based on the current key of PHYSICAL EXAMINATION,
P H Y S I
C A L E X
M N T O B
D F G K Q
R U V W Z
and enciphered the message, departing from traditional Playfair only
by leaving doubled letters unenciphered, as the s's in Gross and crossing:
XELWA OHWUW YZMWI
HOMNE OBTFW MSSP1 AJLUO EAONG OOFCM FEXTT CWCFZ
YIPTF EOBHM WEMOC SAWCZ SNYNW MGXEL HEZCU FNZYL NSBTB
DANFK OPEWM SSHBK GCWFV EK.MUE. A message of
this length would alone suffice for the solution of a Play-fair, and
there were four others in the same key, including one of 335 letters,
beginning XYAWO GAOOA GPEMO HPQCW
JPNLG RPIXL TXLOA NNYCS YXBOY MNBIN YOBTY QYNAI . . .,
for Lieut Kennedy considers it advisable that he pilot PT boat tonight X .
...
These five messages detailed the rescue arrangements, which offered