Musing about uses for salt that don\’t include eating it The Times tells us:
For dads who don’t believe in best-before dates. Put your ageing egg in a cup of salted water, if it floats you can feed it to the wife and children, if it sinks you need to go shopping.
It is, of course, the other way around. If it floats, the air sac has got larger as the egg dries out.
They\’re trying to kill us I tell you!