On pig iron

["Wayne F Johnston"<wjohnsto@dhhs.state.nh.us>]

In the old, old days when ore was smelted to make iron, the molten metal
was poured out into a channel (sometimes in the dirt of the floor) which
had side-channels which ran to holes or molds for the casting blocks or
more nearly finished items.  The foundry crew fancied the molded metal was
attached to the channel as piglets to a sow.  Hence, the casting was
referred to as a pig.  At least such is the story told at one of those
'living museum' type place somewhere in Massachusetts where colonists once
processed 'bog iron'.

This does not answer how shield pigs got their name, of course, but it is
FYI.

(Usual disclaimers)
wayne johnston
NH Bur Rad Hlth
603-271-4842
wjohnsto@dhhs.state.nh.us