galvanism had given token of such things
Galvanism is named after the inventor of the electric cell, Luigi Galvani, professor of medicine at the University of Bologna. It specifically refers to the application of an electrical charge to dead tissue, which was usually demonstrated by making the legs of dead frogs move as if with life. Galvani's nephew, Giovanni Aldini (1762-1834), conducted experiments in London recounted in John Aldini, An Account of the Late Improvements in Galvanism, with a series of curious and interesting experiments . . . [and an] Appendix, containing the author's Experiments on the body of a Malefactor executed at Newgate (London: Cuthell & Martin and John Murray, 1803). In the first canto of Don Juan, written later in the year in which Frankenstein was published (1818), Byron remarks that "This is the age of oddities let loose" (line 1021), and comments on various scientific advances:
Bread has been made (indifferent) from potatoes;
And galvanism has set some corpses grinning. . . .
For a more serious contemporary estimate, written by a major figure engaged in research on this phenomenon who possesses an acute sense of its implications for radical developments in chemistry and physics, consult William Nicholson's account in The British Encyclopedia (1809).