'Foire Commerciale de Bruxelles 1928' by Robert Hughes.

This poster is significant to the previous post of 2 Feb 2012, for on the envelope apparently sent by Marie Antoinette Thomas there are not one but two post office franks which seem fairly clearly to say 1928: one normal round stamp recording the area of posting and the time of dispatch, (the legend Bruxelles NE is clear at least), and a rectangular one promoting the Fair of 1928, as it appears.

The small snag here is that the dates do not match: the poster advertises a fair from 12 to 25 Apr, and the franking advertises one from 7 to 21 Apr!

What are we to make of this? Are there any Brussels Fair nerds out there who want to have their input? Is this envelope not from 1928 at all? Could the dates have been changed quite late in the day, for example after the die for the postal stamp was cut and before the poster was printed, or vice versa?

In all probability, Marie was still alive in 1928 and living at 11 Rue Hydraulique, but we still are short of absolute proof.