Say what???

Gentlemen and ladies

Rode in them merrily,

Or saw small icebergs in open

Water, but in time,

Lager-lovers couldn’t believe their

Eyes – and were roiled – when their pails 

Ran dry and the electromagnets found a

Shorted armature coil.

http://www.themagnetoguys.co.uk/Using_the_Growler.php