Sentence:  "Now for "Swans" & "Ducks", and such like "Birds" of the "Water", it is obvious to take notice how well they are fitted for that manner of life. For those that swim, their "Feet" are framed for it like a pair of "Oars", their "Claws" being connected with a pretty broad Membrane; and their "Necks" are long, that they may dive deep enough into the water. As also the "Neck" of the <WSD>"Hern</WSD>", and such like Fowl who live of Fishes, and are fain to frequent their Element, who walk on long stilts also like the people that dwell in the Marshes; but their "Claws" have no such Membranes, for they had been but a hindrance to those kind of Birds that onely wade in the water, and do not swim." 
Meaning of the word marked with <WSD> tags:  heron.