I've heard that there are mistakes in that book.
I did find this, though.
BPC back purl cross Slip 1 purl st to cable needle, hold in back, knit 2, then purl 1 from cable needle.
FPC front purl cross Slip 2 knit stitches to a cable needle, hold in front, purl l, then knit 2 from the cable needle.
Have you checked for errata on the book?