Sentence:  Three days after, the Great Sun, his brother, sent me another deer-skin of the same oil, to the quantity of forty pints. The most common sort sold this year at twenty <WSD>sols</WSD> a pint, and I was sure mine was not of the worst kind. 
Meaning of the word marked with <WSD> tags:  A Spanish-American gold or silver coin, now the main currency unit of Peru "(also '''new sol''')", or a coin of this value.