Whats That?

An Englishman, an Irishman and a Scotsman got jobs as lumberjacks and each was given an electric power saw. On their first day at work The Englishman cut down a hundred trees. The Scotsman cut down eighty trees but The Irishman could manage only sixty trees. The boss was surprised that The Irishman was so far behind The others, so he said to him, 'Give me a look at your saw to see if it's O.K.' So he switched it on and it went 'brmm, brmm.' 'What's that noise?' said The Irishman.

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