I've done some more work on my timeline. The PoD is the mid-1840's, and again the point is to show what the table might look like if atomic number had been discovered before it was created. Here's a timeline of discoveries: (I'm also assuming that the technology needed to synthetically prepare some of the more unstable elements was developed about 1903.) Here's Mendeleev's table: Most of the names are again from Thande's Look to the West timeline. Please respond if you have any suggestions or critiques. Note: in this timeline, didymium is retained as the name of element 59 due to the X-ray spectra of the particular sample tested.