Votaries of Silver Age Comics almost always pay particular respect to THE FLASH feature. In part this is because many fans consider that the introduction of this hero also served as the starting-point for the Silver Age itself. Certainly, even though one can see a certain amount of carry-over from the "previous age" that ran from 1938-1956, the FLASH displayed elegant illustration from Carmine Infantino and intelligent scripts from John Broome, in such a combination that fans of the period began to expect this level of quality on a regular basis, as opposed to the hit-and-miss approach of the Golden Age.
Though Flash's first few appearances in the SHOWCASE try-out title are enjoyable tales, only in "Master of the Elements"-- Broome's third story with the character-- do all the mythic "elements" come together. There had certainly been dozens of "theme villains" in comic books before Mister Element, but Broome was especially good about conferring a "sense of wonder" upon the various science-factoids associated with a given villain.
The villain makes a standard enough first appearance, though it's amusing that he works in a reference to an obscure element while he robs the Palladium Jewelry Store, presumably named not for the obscure element but for this classic mythological reference.
The Flash shows up during the robbery but is stymied because the far-sighted villain has strung up a series of gold wires to block the hero. On a subsequent occasion, he stuns Flash with the use of sodium;
I won't detail every "element" of the super-criminal's first outing, but suffice to say that Broome manages to work in all the references to the properties of elements in such a way as to invoke a juvenile "sense of wonder." Interestingly enough, this puts the reader in the position of identifying with the villain, since when he narrates his backstory, Element merely says that he became fascinated with the nature of the chemical elements as a young boy.
To be sure, at the story's end Broome wants a spectacular death-trap for Flash, so he magicks up an element that never existed in the real world, and which I strongly doubt ever made a second appearance in Flash's fictional world.
But as I said in the previous essay, this falls into the realm of an extrapolation that is permissible within the boundaries of a story-- even though even I don't know how a "form of magnetic light" could be deemed a chemical element. But since it's the first FLASH story to consistently evoke the cosmological sense of wonder, I've give Broome a pass in that respect.