Sentence:  ... this Raft was so unweildy, and so overloaden, that after I was enter'd the little Cove, where I had landed the rest of my Goods, not being able to guide it so handily as I did the other, it <WSD>overset</WSD>, and threw me and all my Cargoe into the Water ... 
Meaning of the word marked with <WSD> tags:  To turn, or to be turned, over; to be upset; to capsize.