This classic pattern was designed by author and knitting icon Elizabeth Zimmerman in the summer of 1981. Elizabeth "saw (her) first circular needles in the knitting bag of her Auntie Pete on a sandy Cornish beach in 1918".
The pattern calls for a long, 24" or 29" circular needle with one part that is easiest done using a "40" circular needle or struggling with three 24" needles.
The design has been adapted from the Baby Surprise Jacket (also available here). To quote Elizabeth, "..... it looks like nothing on earth when you finish knitting it. Sew up two shoulder seams and you will find the nicest garter-stitch sweater; reversible, with no side or armhole seams and no breaking off or joining-in of wool."