Lynn Avery (1903 - 1979) was a pseudonym used by the author Lois Dwight Cole, an editor for Macmillan. When she went to work there in the 1920s, she struck up a friendship with aspiring novelist Peggy Marsh. The friendship endured, and Cole encouraged her friend, who wrote under the name Margaret Mitchell, to submit her civil war manuscript to Macmillan. She did, and after much editorial work by Cole, the book, Gone with the Wind, was published in 1936.
Cole did not have as much success as a writer. Her horse mystery story received a scathing Kirkus review: “the reader's search for the plot amidst extraneous matter,” it said, “is the only mysterious element in the book.”
When boat-pulling horses are stolen from along the Erie Canal, Gill and Kerry team up after they find hoofprints leading into the swamp. They wonder if the legendary Black Tom Swamp holds the key to the thefts.