From pages dated 4 April 1653, there is information about two ships which have been mentioned in published sources and one ship that has not. The ships all, evidently, were hired by the Amsterdam Directors. One of the three was lost in the catastrophic storm at the end of October 1653 (the Koning David).
The manuscript, very unfortunately, does not mention the ships' captains. The only captain we know is Captain Vogelsang, from the Koning David. Several sources mention his name.
Many lieutenants in early 1652 ended the war, commanding ships. Frederick de Coninck's lieutenant was Dirck Hendricksz.Vogelsang, so that could well be the man who commanded the Koning David. In early 1652, Dirck Vogelsang was lieutenant of the Groote Vergulde Fortuijn.
Here is the data for the three ships mentioned on 4 April 1653:
Koning David
Length: 124 feet
Beam: 29 feet
Hold: 13 feet
Height between decks: 7 feet
28 guns:
12-12pdr
8-8pdr
6-6pdr
2-3pdr
Keurvorst van Keulen
Length: 131 feet
Beam: 30 feet
Hold: 13-1/4 feet
Height between decks: 7 feet
34 guns:
18-12pdr
10-8pdr
4-6pdr
2-3pdr
Schacht den Harculus
Length: 120 feet
Beam: 28-1/2 feet
Hold: 13 feet
Height between decks: 7 feet
28 guns:
10-12pdr
10-8pdr
6-6pdr
2-3pdr
The Schacht den Harculus is the only one of the three ships which has not been previously mentioned in published sources. The Keurvorst van Keulen was called the Elector of Cullen in an intelligence report published in "Thurloe".
I was interested that the Schacht den Harculus carried two less 12pdrs than other 28-gun ships and compensated by carrying two more 8pdrs. This seems strange as there were smaller "28's" that carried the same armament as the Koning David.
I would translate this name as Staff of Hercules. The name is hard to read, but I am quite certain about both "Schacht" and "Harculus". The "den" is written almost as shorthand, and is vertically oriented, between the other two words. I could be mistaken, by my Afrikaans-speaking friend, who reads Dutch literature, agrees that "den" is very plausible.