Post-1960 Rewrites
In 1960, the Stratemeyer syndicate began to rewrite most of the older volumes, many of which became almost unrecognizable in the process. This was done concurrently with the release of a new edition of the series, with picture covers, no dust jackets, and a lavender spine and back cover (replacing the various green bindings that had been used before). Many of the cover paintings were originally dust-jacket paintings that had been added in the 1950s (before which a single common dust-jacket painting had been used throughout any given edition), but most were new with the "purple" edition. In all, 20 were completely rewritten, all but two with modernized titles, while 16 were never released in this edition, evidently having been deemed to be dated beyond repair.
Most of the rewrites were motivated by changing technology (automobiles replacing horses and buggies) or changing social standards, particularly in how Sam and Dinah were portrayed. The Bobbsey Twins and Baby May received what is regarded as the most extreme rewrite; it is a story about the Bobbsey family's adventures trying to find the parents of a foundling baby. Since, by the 1960s, modern social services had rendered the original story utterly implausible, an entirely new novel was written about the twins' adventures with a baseball-playing baby elephant (The Bobbsey Twins' Adventures with Baby May). This, however, had a ripple effect, as the original The Bobbsey Twins at Cherry Corners had been a sequel to the original Baby May. Thus, a second book, The Bobbsey Twins: The Mystery at Cherry Corners, was written. It incorporated only a very little bit of material from its original version.
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