"An old drinking buddy of mine thought it a national scandal the day H&S insisted pubs supply a fresh glass with each drink. He thought it took a few to 'warm the glass up'."

As a callow youth in East Anglia, it was the practice of many of the older men not merely to warm the glass up, but the beer too. They bought a pint, kept it in their hand to warm it up, until they had drunk half, then took it back to the bar and asked for half to be put in on top, so that the lower level would take some of the chill off the new in-pouring. As to changing the glass ...