Phrase: happy as a clam; happy as a clam at high water

[Mullins, Bill CIV (US)]

                Thanks to Charlie for his valuable comment and example. Here are some
                other elaborations of "happy as a clam" from Google Books and the web.
                Apparently, the likelihood of being eaten can make a clam happy too.
                Imputed clam psychology is odd.
        	
                happy as a clam in butter sauce
                happy as a clam in white wine butter sauce
                happy as clams in the sand and the sun
                happy as a clam in the mud
                happy as a clam in thirty feet of water
        	

Variants:  happy as a pig in shit, happy as a pig in mud, happy as a puppy with two peters.  The late lamented (and black) comedian Robin Harris would say "happy as a runaway slave".  
 

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