
1) River of Chile 2) River in South America 3) River in Chile 4) River in The New World 5) River in The Americas 6) River of South America 7) River of The Americas
Found on
https://www.crosswordclues.com/clue/pedrero

(from the article `military technology`) ...was the cannons, or cannon-of-battery, named for their primary function of battering down fortress walls; these typically had barrels of 20 to 25 ...
Found on
http://www.britannica.com/eb/a-z/p/35
No exact match found.