Stat. Theb. II. 564.
"Idem altas turres saxis et turbine crebro
Laxat."
So understood, 1st, the passage is according to Virgil's usual manner, the latter part of the line explaining and defining the general statement contained in the former; and, 2ndly, Pallas kills her enemy, not by the somewhat roundabout and unusual method of first striking him with thunder, and then snatching him up in a whirlwind, and then either dashing him against a sharp rock, and leaving him impaled there, or, as I have shown is undoubtedly the meaning, impaling him with a sharp rock, but by the more compendious and less out-of-the-way method of first striking him with thunder, and then whirling a sharp-pointed rock on top of him, so as to impale him.
From Milton's imitation of this passage, in his Paradise Lost (ii. 180.), it appears that even he fell into the general and double error:
"Caught in a fiery tempest shall be hurled,
Each on his rock transfixed."
Caro's translation shows that he had no definite idea whatever of the meaning:
"A tale un turbo