"rush the growler"--(its derivation)

[Douglas G. Wilson]

>    So, bearing in mind "chase the duck" (drink/fetch/send for beer)
>and "duck" (can of beer), we see clearly that the beer-drinker in
>pursuit of his beer has been likened to a hunter heading for his
>downed duck.  Similarly in "rush the growler" the sending of children
>to fetch beer has been likened to a hunter sending a dog to fetch the
>duck.  The growler (i.e., dog, i.e., the fetcher) has been rushed to
>the tavern to bring back the "duck" (i.e., beer).

Please correct me if necessary, but it was the pitcher or can or whatever
(which was used to carry beer, etc.) which was called either "the growler"
[HDAS, 1885] or "the duck" [HDAS, 1901], right? Apparently, besides "rush
the growler" there were "hurry the can", "chase the duck", "roll the rock".
"Growler" = "pitcher" appears in the "Century Dictionary" (1889, I think).
It doesn't look to me as though "growler" referred to a person (or dog).
[W3 attributes "duck" = "urinal" to its pitcher shape.] What is "roll the
rock"? [Cf. Rolling Rock brand beer: any connection?] Is the image that of
a keg of beer being rolled home from the corner shop? [Or is the expression
from the brand name, perhaps?]

If "growler" actually originated as a name of a container, it is difficult
to explain (at least, difficult for me). I suppose one might speculate an
alteration of "[holy?] grail" (not an obviously natural alteration
phonetically though IMHO) ... or one might speculate "grueller" =
"gruel-pot" in a Scots or dialectal form (Scots "growl" is sometimes given
as = "gruel") (but I don't find this "grueller"! ... although there is an
analogous "porridger").

-- Doug Wilson