Whenever any owner or master of a ship or boat within the haven or streams, loaded [with merchandize] of burgesses or outsiders, proves obstinate and refuses to come before the chamberlains to take an oath, as per these ordinances, then his ship or boat is to be attached without further ado. The ship or boat is to remain under attachment until he [i.e. the owner or master] has paid a 20s. fine for his resistance to authority, to be levied to the profit of the town. And notwithstanding [this fine], the owners are to pay their customs to the town without any pardon.
[The "streams" referred to were probably the local rivers that fed into the estuary channels surrounding the site of Yarmouth.]