Sentence:  Examining this piece of worked stone, which once belonged to a prehistoric man living in that valley, we find it fairly well polished, though the action of countless years has slightly "weathered" or disintegrated its once smooth surface. In the center, a groove has been cut, and the ends of the stone rise slightly from the middle. It is rather crescent-shaped. It must have been tied to a line, and this stone <WSD>gorge</WSD> was covered with a bait; the fish swallowed it, and, the <WSD>gorge</WSD> coming crosswise with the gullet, the fish was captured. [...] In the Swiss lakes are found the remains of the Lacustrine dwellers. Among the many implements discovered are fish-<WSD>gorges</WSD> made of bronze wire. When these forms are studied, the fact must be recognized at once that they follow, in shape and principle of construction, the stone <WSD>gorges</WSD> of the Neolithic period. 
Meaning of the word marked with <WSD> tags:  A primitive device used instead of a hook to catch fish, consisting of an object that is easy to swallow but difficult to eject or loosen, such as a piece of bone or stone pointed at each end and attached in the middle to a line.