Living as we do in the lightning capital of the United States, we can confirm that this is indeed Adamastor, "a hideous phantom whose face is scarred by lightning and whose eyes shoot fire."  From St. Nicholas magazine, 1908.

Atmospheric electrical discharges often get demonized, but they're sparked by an angel: "Nang Make Kala, an angel who causes lightning."  From Five Years in Siam from 1891 to 1896 by Herbert Warington Smyth, 1898.

 Here's light on an important subject, from an 1893 advertisement.

"And then there came a blinding flash," from Kidnapped by Robert Louis Stevenson, 1898.