Stowed atop the chain were several implements—notably a matched pair of short axe-like tools, packed in oakum to keep them from clanking about "and waking the ducks," as van Hoek liked to phrase it. Jack removed these one by one and hung them about his shoulders on their braided cotton straps. When the only thing remaining in the tun was the chain, Jack tipped it so that the water of the Guadalquivir spilled in over its top. Within a few moments the weight of the chain had driven it down below the surface. Immediately the line he’d lashed round the anchor cable began to take that weight. It tightened, but his knotwork held fast and it did not slip down.