Tea consumption increased dramatically during the early nineteenth century and it is around this time that Anna, the 7th Duchess of Bedford is said to have complained of "having that sinking feeling" during the late afternoon. At the time it was usual for people to take only two main meals a day, breakfast, and dinner at around 8 o'clock in the evening. The solution for the Duchess was a pot a tea and a light snack, taken privately in her boudoir during the afternoon.Later friends were invited to join her in her rooms at Woburn Abbey and this summer practice proved so popular that the Duchess continued it when she returned to London, sending cards to her friends asking them to join her for "tea and a walking the fields." Other social hostesses quickly picked up on the idea and the practice became respectable enough to move it into the drawing room. Before long all of fashionable society was sipping tea and nibbling sandwiches in the middle of the afternoon.
Occasionally you will see hotels serving a ‘high tea'. Traditionally, the upper classes would serve a ‘low' or ‘afternoon' tea around four o'clock, just before the fashionable promenade in Hyde Park. The middle and lower classes would have a more substantial ‘high' tea later in the day, at five or six o'clock, in place of a late dinner. The names derive from the height of the tables on which the meals are served, high tea being served at the dinner table.
The "at home" tea became a common practice. After deciding on a day of the week to hold at home hours, the hostess would send announcements to friends, relatives, and acquaintances. On that particular day of the week one would remain at home all day and receive visitors. Some entertainment might be provided for the guests, but usually conversation, after the model of the French salon, was the primary entertainment. Tea and cakes, sandwiches, or other niceties were be 
served. If sent an at home notice it was expected that unless regrets were sent that all who received a notice would attend. There was at least one person holding an at home day on any given day, and social ties were established as women saw each other almost every day at different houses.
Tea was a valuable commodity, and stored in locked tea caddies for which only the woman of the household held the key. In allowing the eldest daughter, or friend, to serve the other beverages, and reserving the privilege of serving of tea to only herself, she sets levels of social significance. This is an interesting parallel to the lord of the house serving the tea in China. In both cases it is the host with the most power who serves the tea, in spite of the gender differences. Men in nineteenth century Britain were higher on the public scale of social hierarchies, but the woman was in charge of the household, and creating the genteel atmosphere connected with formal social visits. As a result she was more powerful within the house than the man. Even when the British "lord" of the house was present it was the woman's responsibility to serve tea.
The hostess also adds the sugar and milk or lemon to the tea for the guest. These substances were common and inexpensive enough to serve often and to many guests. However, the cultural legacy from when both tea and sugar were rare and expensive luxury goods, created a situation in which the hostess desired, or was expected, to be in control of the amount consumed. When sugar and tea were first introduced only the aristocracy were able to possess them.
In cricket, the second and usually shorter of the two intervals during a match lasting a full day or more is known as the tea interval, and also (more formally but less commonly) the afternoon tea interval. The interval is an opportunity for the players and umpires to partake in light refreshments. Some international cricketeers have been known to have as many as three cups in a twenty minute break.
For international nuances and more links. Wikipedia.Smith, Michael. The Afternoon Tea Book. New York: Atheneum, 1966.
Mintz, Sidney W. Sweetness and Power: The Place of Sugar in Modern History. New York: Penguin Books, 1985.
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