This is a letter, dated September 10th, 1943, to John R. Neill from Reilly & Lee, the publishers of the Oz books. The letter is written by Margery Peterson, secretary to Frank O'Donnell, the president of the company; she states that they have not yet received the new Oz manuscript, and laments the fact that a new Oz book will probably not be published that year.
I find this letter rather poignant for two reasons. First, this means the tradition of a new Oz book every year was coming to an end after a 30 year run. From 1913 through 1942, a new title had been published each year. The next book in the series would not be published until 1946, and several more titles were added sporadically after that.
More importantly, Neill died nine days later, on September 19th, 1943, leaving a void in the Ozzy universe. Starting in 1904, he illustrated 35 Oz books, not counting the Little Wizard series and other L. Frank Baum fantasies. His artwork was an indelible part of Oz, and after working for so many years with Baum and his successor, Ruth Plumly Thompson, he took over authorship of the Oz series. Three books were published with Neill as author and illustrator, and while these titles tend to rank low on the scales of favorite Oz books, the tradition of a new story each year was upheld. This year is the 70th anniversary of his death.