Circa 1905-1908 - Both examples above and below are the earliest versions of IVES glass dome platform. Note that they have 32 individual panes of glass and a red girder strip below the bottom windows. For what it's worth I think the example above is earlier than the one below. The 121 pictured above has butterscotch striped benches and the dark green posts. Note also the two color litho (red/black)  to the base. The No. 121 pictured below has red cherry striped benches, the brown, natural wood looking posts and three color lithography to the base, with pretty gold highlights.

Circa 1908-1909 - Just to prove no matter how rare something is there's still lots of variation.  Here's an early dome on a base with the small brass plate and red cherry stripped benches. Note also 8 posts and 2 benches.

Circa 1908-1910 - The 121 Glass Dome now has only 12 panes of glass (instead of the 32 above), note that the girder below the window is now cut in half. The posts are the light natural wood color with scallop work only on the top and bottom and that the base although tri-colored now has a small plate in the front "The IVES Minature Railway System". These plates usually only show up on pieces made around 1909. Ives used this 12 pane window design for only a short period of time and they are very difficult to find today.

We think someone may have switched the colored and clear panels on this some time over the past 95 years but this shows clearly how the 12 panels were laid out. We don't know why, but this design was very short lived and is extremely hard to find.

Circa 1910 - This one has an early base (with plate), painted benches and scallop work around the edges, but only 8 panes of glass. Compare the three domes above and the one below. These 4 glass domes were probably all made through a 3 or 4 year period. Three of the four have the small brass plate on the base, first associated with 1908 or 1909, but known to appear on later vintage items. Note the change in the glass panels, number of posts and benches.  

Bases are painted white, but benches are lithographed Cast pieces still orange/red with scallop work around the edges.

Circa 1911-1913 - Note that this version still has the lithographed base, but the benches are painted. Also note that there are now four benches, 8 panes of glass and only 6 supporting posts. The posts are the clear finish type. The dome still have the orange arch supports.

Circa 1914-1920 - Base is now painted, four benches, clear smooth posts, green leaded glass in middle panes, glass supports are painted red, later (below) are green.

Circa 1920-1927 - Last version - painted base with 4 benches, later posts with more bevels at base, glass supports are not painted. Below is end view of same dome.