Suspecting a kind of malice in Shade's verses while he was lying naked in the tub, I checked for "euphemisms" related to "dock/docking," after I remembered having once received a collection of images of coupling dragonflies, under the heading "docking."  
I don't know if this same word was employed euphemistically, in this sense, in the sixties.
 
Inspite of never having read Jonathan's Swift's complete works, I was able to explore his "Tale of a Tub" - superficially -  thanks to the internet. Also Swift mentions Zembla in it. (it's actually, Nova Zembla.)  Here is the link: A tale of a tub, written for the universal improvement of mankind: ... -
Jonathan Swift - 1704 - 322 ... Mountain in Nova Zembla ; there Momus found her extended in her Den, upon the Spoils of ...
books.google.com.br/books?id=TVQJAAAAQAAJ...
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