Sentence:  There had been a “cosmium” and “neutronium” (“element”), too, to say nothing of “archonium,” “asterium,” “aetherium,”and the Ur-element “<WSD>anodium</WSD>", from which all the other elements supposedly were built. 
Meaning of the word marked with <WSD> tags:  A hypothesized substance from which all other elements were formed.