This document discusses the cultural and social history of tea drinking in Britain. It explores how tea was once expensive and smuggled, but fueled the industrial revolution by providing stimulation. It was common for the working class to put milk in their tea first, while the upper class would put milk in last. Over time, putting milk in first became seen as a marker of lower class status. The document also discusses how the modern tea bag was designed to brew quickly in a mug, meaning putting milk in first can interfere with the brewing process.