The Rubaiyat of Omar Khayyam:
1910 T.N. Foulis Maurice Greiffenhagen Miniature Edition

This 1910 T.N. Foulis edition is a miniature copy with color illustrations from Maurice Greiffenhagen (but the “End Papers” are from Robert Hope). It is presumably of the ‘The London Booklets’ series by the publisher. It was printed by T. and A. Constable in Edinburgh.

Of particular note is how the year is displayed: MDCCCCX. Now, this is, of course, Roman Numerals. However, the format is not standard. If you put it into a converter it will error out and say invalid. Apparently, MDCCCCX was sometimes used instead of MCMX. This article was how I discovered the strange usage and an example of it. Definitely threw me for a loop when I was trying to date it!

Update 05/2023: Updated the layout, added more pictures, and tweaked page copy.