Some of the traditional beliefs associated with the rat are similar to the ‘mouse’ (See Mystical WWW Mystic’s Menagerie : Mouse). The rat appears to be an animal of mixed fortune.
Like the mouse, one entering the house or chewing on furniture or linen was believed to be an omen of imminent death. Yet if the rats suddenly left this was seen as a sign that the house was about to collapse. Getting rid of what are now seen in many countries as vermin was once believed to be successful in Scotland (UK) if the following rhyme was recited:
‘Rats and mice,
Leave this poor person’s house,
Go on away over to the mill
And there you’ll get your fill.’
Rats were once a common sight aboard ocean going vessels. Likewise the action of rats suddenly deserting a ship was seen to indicate that disaster was about to strike, the likelihood being that the ship was about to sink. Although the sight of rats aboard a new ship, waiting in dock, was thought to be a positive sign, perhaps because they were seen before the ship touched water and therefore could be cleared. Perhaps too because in some countries rats have been thought to carry the souls of the dead. As a result the habits of the rat have been closely watched by sailors the world over to indicate the fortune of the men at sea.
One rather strange but understandable belief indicates that children who had just lost their milk teeth were advised to appeal to the rat for strong second teeth (as rats were known to have such teeth).