In Ireland today a "naggin" is a small bottle of liquor in
the familiar hip flask shape. (A bottle nearly twice as large,
less easily smuggled into events where alcohol is banned, is
called a shoulder or daddy naggin.) In Ulysses the
word carries that meaning but can also refer to the liquid
measure contained in naggin bottles, or to drinking vessels of
roughly the same size. It comes from the Irish naigín
or noigín (possibly an offshoot of the English
"noggin"), which originally named a kind of small wooden pail
that served as a drinking cup.
In Calypso Bloom sees an old woman trudging out of a
liquor store quite early in the morning, "clutching a
naggin bottle by the neck." Here the word clearly refers
to a commercial bottle, but in Scylla and Charybdis
Stephen uses it in the older sense when he speaks of Socrates
being put to death: "neither the midwife’s lore nor the
caudlelectures saved him from the archons of Sinn Fein and their
naggin of hemlock."
Exactly how much fluid is being referenced in these two
passages hardly matters, but "naggin" can indicate a
precise amount, and in its perversely particular way Ithaca
forces the reader to assign some little importance to it.
The Blooms' kitchen shelves, the chapter observes, hold "a jug
of brown crockery containing a naggin and a quarter of
soured adulterated milk, converted by heat into water,
acidulous serum and semisolidified curds, which added to the
quantity subtracted for Mr Bloom’s and Mrs Fleming’s
breakfasts, made one imperial pint, the total quantity
originally delivered." A British "imperial pint" is 568 ml and
traditionally a naggin was one quarter of a pint, so it would
seem that 177.5 ml of the milk remains (568 x .25 x 1.25). But
naggin bottles of liquor in Ireland today hold 200 ml. By this
standard 250 ml of spoiled milk would be left in the crockery
jug.
Terence Dolan's Dictionary of Hiberno-English cites a
couple of colloquial uses of the word and several literary
examples, including this one from the title song of Finnegans
Wake: "when a noggin of whiskey flew at him."
Since this action precedes the crucial moment at which some of
the precious liquor splashes on Tim and revives him, it seems
likely that the "noggin" is a drinking vessel rather than a
bottle, and indeed some versions of the folk song refer to "a
bucket of whiskey" rather than a noggin or naggin. Dolan
quotes from Peter Martin's 1921 article "Some Peculiarities of
Speech Heard in Breifny" to the effect that a naggin is "a
wooden vessel made of tiny staves, one of which is longer than
the others and forms a handle." Dublin pubs had probably
abandoned such wooden cups for metal and glass ones by Joyce's
time, but it seems reasonable to assume that in his Dublin a
naggin could be either the "small mug or drinking-vessel" of
Dolan's traditional definition, or the glass bottle of modern
liquor stores.
The traditional wooden cup is the subject of a scholarly
study recently published by Claudia Kinmonth. The essay,
titled "Noggins, 'the nicest work of all': traditional Irish
wooden vessels for eating and drinking," first appeared in Irish
Architectural and Decorative Studies: Journal of the Irish
Georgian Society 18 (2015): 130-51. After winning an
award from the Irish Antique Dealers' Association in 2016,
Kinmonth published a revised version in Folk Life: Journal
of Ethnological Studies 55.1 (2017): 46-52.