He assumed the empty spaces belonged to elements that humans had simply not discovered yet. 🔮 The Famous Predictions
How the differs from Mendeleev's original version The biography of Mendeleev himself Periodic Table of Elements - American Chemical Society gthbjlbxtcrfz nf
The direct translation of your prompt from a Russian keyboard layout is , which translates to "Periodic table — produce a feature." 🔬 The Periodic Table: The Predictive Power of Gaps He assumed the empty spaces belonged to elements