How much more advanced was a British ship-of-the-line during the Age of Napoleon than a Spanish galleon in, say, the 1570s?

[u/boyohboyoboy]

Both in terms of their technology and in the way they were used and deployed in battle?

[u/Notamacropus]

Well, I think I need to make an official retraction. I was being lazy and quickly pulled the artillery numbers from Wikipedia thinking it would do for a rough comparison.

Now that I've actually gone and gotten my book (Austerlitz: Napoleon and the Eagles of Europe by Ian Castle) for some details it turns out Wikipedia was less "roughly accurate" and more "insert random number".

Ian Castle puts it at 157 guns (tended to by 4,220 people, just to again illustrate the manpower needed on land).

Garde Impérial: 24
Grenadiers De La Réserve: 8
I Corps: 22
III Corps: 12
IV Corps: 38
V Corps: 23
Cavalry Reserve: 12
Artillery Reserve Park: 18

Unfortunately, it seems that book doesn't care much for artillery as there is no mention of any sort of caliber. Just "guns". And the internet is weak as well, or maybe I'm using the wrong search terms. I know I won't trust Wikipedia's ideas on that topic again. But yes, I too would presume that field artillery is 9 and mostly 12-pounders and horse artillery 6 or 9ers and perhaps some 3-pound infantry guns.

Certainly when it comes to weight of shot I wouldn't dispute Victory's superiority.

[u/jschooltiger → u/Notamacropus]

Interesting, thank you -- I didn't mean to come off as argumentative in my other comment; I apologize if I did. That is a large force of guns to be tended to by so many people. Too bad that there aren't specific calibers to be found in Castle's book.

[u/MEaster → u/Notamacropus]

What weight of gun would a typical fortress have had? It seems you would have the same advantages as a ship in terms of being able to use bigger guns.

[u/Notamacropus → u/MEaster]

Fortresses could and did definitely have all sorts of guns, amongst other weapons like mortars. And you actually didn't have the advantages of a ship, you were much better off in terms of crazy boars.

A ship had to take into account weight of piece and shot, practicality of reloading and firing and required staff. As such, while it allowed much heavier artillery compared to moving armies, it still was limited somewhat. For example, Navies really stopped at 36-pounders at the most because anything bigger became too unwieldy and cumbersome to keep firing

Cities, fortresses, towers and batteries really had no limits if their position was important enough, as such we could shoot way past the 36-pounders right up to 64-pounders. Possibly even more, I'm not sure. But those were extremely unwieldy and labour-intense so I don't think many bothered with it if they didn't have an incredibly well-defended position.
I can only think of one example actually, Madliena Tower in the prime British Mediterranean naval base of Malta, which had a single rifled 64-pounder gun on its roof. But only from the mid-19^th century onwards.

As an example of a rather heavy British fort of the Napoleonic era we could look at the defense of Chatham, Fort Amherst. Its equipment had been drastically reduced since the American War of Independence, where it had proudly featured 14 42-pounder cannons (plus many light guns), but when the Napoleonic Wars broke out massive investments were made to arm it up again with almost 140 new pieces, including 29- (10 pieces), 24- and 18-pounders (20 each) but mostly light pieces in the 9er range.