I had forgotten that I had solved the question about who Anthonis Fappenlain was

The First Dutch War, Vol.V, mentions Anthonis Fappenlain as being in Michiel De Ruyter's squadron at the Battle of Scheveningen. On April 24, 2004, I had posted a piece about De Ruyter's squadron that explained that Anthonis Fappenlain (or Foppenthey) was Thijs Tijs Tijssen Peereboom's lieutenant. Apparently, he actually commanded the ship in the battle, so he was called "lieutenant-commander" or luitenant-commandeur. The ship was the Noorderkwartier ship Peereboom (24 guns). I had forgotten that I had solved this issue, in part thanks to Dr. Elias.