Pieter Aldertszoon's ship in June 1652 was the Eenhoorn of 1625

Carl Stapel says that the ship commanded by Pieter Aldertszoon at the start of the war was the old Eenhoorn, built in 1625. Ron van Maanen makes news by saying that the dimensions of the Eenhoorn were 125ft x 29ft x 11-1/2ft with a height between decks of 6-3/4ft. At some date, perhaps July 1654, the Eenhoorn's armament was 7-12pdr, 13-10pdr, 4-8pdr, 2-6pdr, 2-4pdr, and 2-3pdr guns. The Eenoorn was last mentioned in 1655. Sometimes, the length is said to be 124ft. The size is usually listed as 220 lasts. Sources:

1. Ron van Maanen, unpublished manuscript "Dutch Warships 1600-1800", undated, but circa 1992
2. Carl Stapel, personal communication about the Eenhoorn, 2006