In his weekly ‘The Bar Man’ column, Jeff Hoyle discusses fair measures… Like a head on your beer? So do the publicans. The more froth that you have in your glass, the less beer you receive and the more air you are paying for. In the north of England, where a decent head on a pint was the norm, several systems were introduced to make sure the drinker received full value. Common in Lancashire when I was first frequenting pubs was the measured dispense, normally a horizontal or vertical glass cylinder that served a measured half pint. Obviously, if there was any spillage, the pint could not be to…