This Thomas Nelson and Sons edition is packed with content. It looks to share a great deal of overlap with the 1932 Walter J. Black Companion Classics edition. It has:
Amongst other typical Rubaiyat related content sections.
Based on the bibliography in the back of the book, it would seem that it could be maybe dated to 1899/1900, since 1899 is the latest it goes. Assuming that isn’t just where there happens to be a drought for however many years…
The pages are incredibly thin, you can see the text of future sides/pages easily. It’s sometimes hard to read for that reason.
This edition is part of a greater collection from Barbara Campbell that I purchased a portion of.