Happy New Year!
John R. Neill provided a lovely frontispiece illustration for Reilly & Britton's 1915 edition of Darby O'Gill and the Good People. This book was first published in 1903 by McClure, Phillips and Co., and a later edition was published by Reilly & Lee. This Reilly & Britton printing seems to be a bit unusual, as I could currently find no listings for other copies.
Neill's frontispiece is the only illustration in the book, which is unfortunate. This collection of Irish tales would have been right up his alley for inspired imagery. The book was the basis for Walt Disney's 1959 movie Darby O'Gill and the Little People.
The book was written in 1903 by Hermione Templeton, who remarried in 1905 and became Hermione Templeton Kavanagh.