Irish yoke

Irishman walks into a pub. He orders 4 double shots of whisky and a pint of Guinness.

The bar man pours out the shots and lines the 4 glasses in a row. He then moves away to procur the pint of Guinness. Upon his return he is surprised to see the four shot glasses empty before the Irishman.

"Jeepers you drank that whisky fast."

The Irishman replies." And you would be drinking just as fast if you had what I have!"

The bar man asks. " just what do you have?"

" 50 cents" the man replies.