the ship of the line pictured in Bowzer’s post. She was what what was called a "second rater", "first raters", like HMS Victory, were 100+ guns. Fourth and fifth raters (60+ guns) were considered big enough to fight "on the line". For comparison, the USS Constitution, 44, (Old Ironsides) was a very large and powerful frigate, and although one of the most advanced and deadly ships of her class in her time, was still not considered strong enough to serve in the line. In the late 18th and early 19th century, the typical and most common size for a ship of the line was a third rater, a 74 gun two-decker.

Many second and first rate ships proved to be poor sailors, and were often cut back to this size by removing a gun deck and shortening the rig, to make them more manageable. But this often led to problems too. A vessel designed for one size might not work well if arbitrarily altered to other dimensions. It had a lot to do with the captain's preferences, too. Yankee men-of-war were notoriously over-sparred and over-gunned, and although respected and admired by the Royal Navy, usually had their rigs cut back and some guns removed if they were captured, in an effort to improve their performance and durability.

In modern parlance, a ship of the line would be called a battleship today. Frigates served the role of modern-day cruisers; pickets, scouts, escorts, recon, and commerce raiding. They were better suited to independent action than fleet duty.

Today, a frigate is a small ship, smaller than a destroyer. The ship I served on in 1968 was called a "frigate", but since that time, ship nomenclature has been changed to fit uniform NATO standards. Nowadays, she would be reclassified as a destroyer.

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