Exodus 9:22-24

Verse 23

The Lord sent thunder - קלת koloth, voices; but loud, repeated peals of thunder are meant.

And the fire ran along upon the ground - ותהלך אש ארצה vattihalac esh aretsah, and the fire walked upon the earth. It was not a sudden flash of lightning, but a devouring fire, walking through every part, destroying both animals and vegetables; and its progress was irresistible.
Verse 24

Hail, and fire mingled with the hail - It is generally allowed that the electric fluid is essential to the formation of hail. On this occasion it was supplied in a supernatural abundance; for streams of fire seem to have accompanied the descending hail, so that herbs and trees, beasts and men, were all destroyed by them.
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