During the industrial revolution the Victorian era working class people enjoyed evening meals of prepared foods such as cold meats, pickles, cheese, bread and butter and good hot tea. Long, hard days at work made this a necessary way to get a meal on the table fast. This meal was eaten at what we know as our dining room table. The "high table" gave the meal the name "high tea".
Remember that Afternoon Tea was eaten at low tables in nice comfy chairs. This was a social time in the late afternoon between the light noon lunch and late dinner. Mostly enjoyed by the upper class, sweets and savories were served with hot tea. Finger sandwiches satisfied the tummy while sweets lifted the spirits.
If you go to a tea room in the USA you may notice a "common mistake" made using the term "high tea" when the appropriate "afternoon tea" would be correct. Often after a tea room opens and knowledge and research are persued, there will be a correction made on the menu. Since "afternoon tea" is labor intensive (unless heaven forbid they buy at Sams Club) expect to pay $15.00 t0 $50.00 or more depending upon whether you are at a small tea room or a grand hotel.
Valentine's Day is a great time to find a lovely tea room near you...Check out these websites to see what is nearby:
http://greattearoomsofamerica.com/ and http://http://www.teaguide.net/