Sentence:  ... as our little Traffick with the Natives was hitherto upon the Faith of their first Kindness, we found some <WSD>Knavery</WSD> among them at last; for having bought some Cattel of them for our Toys ... one of our Men differing with his Chapman, truly they huff'd him in their Manner, and keeping the things he had offered them for the Cattel, made their Fellows drive away the Cattel before his Face, and laugh at him ... 
Meaning of the word marked with <WSD> tags:  An unprincipled action; deceit.