The Hornby Book of Trains (1926)
The 1925 experiment seemed to be a success, because in 1926 Hornby issued a new "The Hornby Book of Trains", with a cover showing the green Great Western Castle-Class loco, 4079 Pendennis Castle (built circa 1923).
The cover of the 1926 publication was again undated and unnumbered (apart from a slightly cryptic publication code on the back cover), but the first inside page did make amends by making a point of saying that this was the 1926 version, and describing how its contents related to those of the previous one, now explicitly identified as the 1925 version.
The editors still seemed to be "pulling out all the stops" and not holding anything in reserve for future issues, as the 1926 issue editorial section now tried to describe and illustrate all the working parts of a steam locomotive.
The operation of the more important railway mechanisms
Page 23 onwards is catalogue material.