Things were getting desperate for the members of the jungle expedition. They had been travelling in ever narrower circles for three days, their supplies were running low and the helpers they hired insisted on returning to their homes. Everyone thought that they would be lost for ever.
Happily, one of the natives offered a solution. He held up for all to see a large jungle insect which looked like some sort of mantis.
"The insect always points North," he said. "I will leave you now but if you follow the pointing insect, you can find your way out without me."
The explorers were happy to follow the insect. Indeed, it maintained a steady heading at first and they seemed to be making progress. Then a day passed. Then another one passed. The huge insect began to twitch and shake ever more erratically.
They knew that they were lost.
"Forget it!" one of them shouted in frustration. "This insect is mad! It's insane I tell you! It points every which way and we're lost. This is hopeless!"
"How can you tell that?" the others asked. "How can the insect be mad?"
"Can't you all see?" he cried...... "It's non-compass-mantis."