Hello, I have recently been recreating plans according to a drawing of a fourth rate (courtesy of Van De Velde, The Younger) I found in the NMM/RMG archives. However, a problem arose concerning the amount of guns of the actual ships and the depicted ship. (See below)

The ship has 9 gunports shown on its lower deck, 10 on its upper deck, and 3 (though one is likely unused) on the quarterdeck, giving us 18 guns for the lower, 20 for the upper, and 4-6 for the quarterdeck. However, information on the Assurance of 1646, which is said to be the ship depicted, gives a different picture.

(information from threedecks.org , very trustworthy)
it seems that the lower and upper decks had their gun counts switched, but the description of the NMM drawing further confirms that the Assurance had indeed that layout of guns. That's the first issue.
-

The second issue, as stated in the description of the portrait itself (pictured above), is that Assurance had been sold out of the navy before the drawing was made (1701) - so that makes her even less likely to be the depicted ship - and the second most likely option, the Seahorse, was not even a fourth rate (from what i could find) and was instead a 6th rate of a measly 20 guns. So annoying!
That's when I decided to go look for a ship that might match the broadside depicted and was still in the navy by 1701. The ship I landed on was Adventure, of around 42 guns.

And there on her armament you see:
- 18 guns on her lower
- 20 on her upper
- 4-6 on her quarterdeck
A great match! And it was indeed in the navy in 1701!
However... This "answer" bothers me.
Yes the Adventure fits the ship depicted by Van de Velde, but it seems wrong to me that actual experts would get the ship wrong when having access to great archives containing hundreds of ships whilst I was able to "solve" the mystery so simply through an internet archive!
- Could it be that I managed to actually figure out what the depicted ship is?
- Could it be that the drawing is indeed of the 'Assurance', but that it was flawed?
...I don't know about either of those but if you think you have an answer, please, do let me know!

The ship has 9 gunports shown on its lower deck, 10 on its upper deck, and 3 (though one is likely unused) on the quarterdeck, giving us 18 guns for the lower, 20 for the upper, and 4-6 for the quarterdeck. However, information on the Assurance of 1646, which is said to be the ship depicted, gives a different picture.

(information from threedecks.org , very trustworthy)
it seems that the lower and upper decks had their gun counts switched, but the description of the NMM drawing further confirms that the Assurance had indeed that layout of guns. That's the first issue.
-

The second issue, as stated in the description of the portrait itself (pictured above), is that Assurance had been sold out of the navy before the drawing was made (1701) - so that makes her even less likely to be the depicted ship - and the second most likely option, the Seahorse, was not even a fourth rate (from what i could find) and was instead a 6th rate of a measly 20 guns. So annoying!
That's when I decided to go look for a ship that might match the broadside depicted and was still in the navy by 1701. The ship I landed on was Adventure, of around 42 guns.

And there on her armament you see:
- 18 guns on her lower
- 20 on her upper
- 4-6 on her quarterdeck
A great match! And it was indeed in the navy in 1701!
However... This "answer" bothers me.
Yes the Adventure fits the ship depicted by Van de Velde, but it seems wrong to me that actual experts would get the ship wrong when having access to great archives containing hundreds of ships whilst I was able to "solve" the mystery so simply through an internet archive!
- Could it be that I managed to actually figure out what the depicted ship is?
- Could it be that the drawing is indeed of the 'Assurance', but that it was flawed?
...I don't know about either of those but if you think you have an answer, please, do let me know!