Yes, agree this is a very interesting and complicated topic. Here's a quote from Chapter 21 of my on-line book:
"Amarna art emphasized the life-giving nature of light. Yet, during the Amarna Period an apparatus was invented or refined that focused the rays of the sun in a highly destructive manner. Demonstrations of this technology are described in Exodus 19:16-24; 20:18-21, 1 Kings 18:22-38, and 2 Kings 1:9-14. The ancients were able to produce optical lenses, as evidenced by those used to form the eyes in Old Kingdom statues. They also knew or learned how to make reflective collimating mirrors. According to extra-Biblical records, such mirrors were used to set ships on fire from a distance."
The above text cites a book called "The Crystal Sun" by Robert Temple.
There is also discussion on the fire power of Elijah in Chapters 25 and 26 of my book.
A later king, Ashurbaniapal of Assyria, was fond of boasting about the terror-inspiring and blinding splendor of Ashur and Ishtar that he directed toward his enemies.
© Charles N. Pope, US Library of Congress. All rights reserved.