What was the most common number of artillery decks on sailing ships of the line?
The first English two-decker was built in 1514. In the middle of the 18th century, larger three- or even four-deckers with 98 to 140 guns were built, that served as admirals' command ships. Those have however proven highly unstable and difficult to manouvre, so large two-deckers were more common as the most practical ones.
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