sentences:  It was intended to function as a specialised artillery tower, housing gunpowder weaponry capable of suppressing attackers on the far side of the river.The Wensum was quite narrow at this point, however, and the tower's defences would have been of relatively limited value if the enemy successfully crossed over.There are fragmentary historical references to an earlier tower in the area, responsible for collecting tolls and acting as a prison, but it is unclear if this was on the same site as the Cow Tower, or refers to a different tower in the area.