1920 Agriculture and Science Issue
The Post Office issued six stamps in the 1920 series. The 100 through 400 share a common implementation, with the 400h appearing in two distinctive types, but in preparing the 500h and 600h stamps, some small revisions occurred.
| Original Design | Modified design |
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The major differences in the two implementations are: the later stamps have a somewhat bolder and rougher appearance, the ornamentation of their value tablet is slightly altered, their ribbon is broader and its lettering is a bit different, some of their shading lines are missing, and the face on their allegorical figure is more expressive.