There seem to be several versions of Thomas Talbot Bury's color plate (edit: likely an aquatint per the comments below) "Excavation of Olive Mount" (part of a collection entitled "Coloured Views on the Liverpool and Manchester Railway"; the 1831 release of this collection is available on Google Books).
Version 1 (can be seen here): the spokes on the drive wheels of the locomotive in the foreground are well-defined, many of the people are wearing brightly-colored shirts, and there are no trees on the bridge in the background.
Version 2 (can be seen here): very similar to version 1, but the palette is muted (although this may be attributable to the digitization process or a deliberate choice made when the illustration was colored). There are other subtle differences as well, including:
- The shape of the clouds near the top-middle of the image is different
- The locomotive's smokestack is missing a ring roughly halfway up its height
- The spokes of the locomotive's drive wheels are much less distinct than in version 1
- The landscape visible beyond the bridge on the right side of the tracks is substantially darker than the landscape immediately before the bridge
Version 3 (can be seen here): very different from the versions described above; the differences include:
- All the passenger carriages are enclosed
- There are trees on the bridge; it's also much taller and its arch is pointed
- There's no second locomotive in the background just before the bridge
- A second bridge is visible beyond the first
- The pattern of the rocks is very different
- The tracks are not a straight line, but bending near the horizon
Given that aquatint allows copies of an illustration to be produced from a master copy, why are there multiple versions of "Excavation of Olive Mount"? This site says there were six releases of the collection that contained it (between 1831 and 1834); were new versions of the work created for some of these releases?