Possible Clues:

• It will pull a goat but only when upset
• Barge helper
• Vessel perfectly captures posh Britain
• Water-tower
• Workers attack case for British harbour vessel
• Pot including good grass: one should offer a drag
• Powerful vessel used to pull larger ones
• A tower of strength, in the main
• Vessel drawing mild disapproval when sticking in a bog, anyhow
• Small tower