The old-fashioned plan of allowing a teaspoonful to each person, and one over, is still practised. Warm the teapot with boiling water; let it remain for two or three minutes for the vessel to become thoroughly hot, then pour it away. Put in the tea, pour in ½ to ¾ pint of boiling water, close the lid and let it stand for to tea to draw from 5 to 10 minutes; then fill up the pot with water. The tea will be quite spoiled unless made with water that is actually boiling, as the leaves will not open, and the flavour not be extracted from them; the beverage will consequently be colourless and tasteless, - in fact nothing but tepid water. Where there is a very large tea party to make tea for, it is a good plan to have two teapots instead of putting a large quantity of tea into one pot; the tea, besides, will go father. When the infusion has been once completed, the addition of fresh tea adds very little to the strength; so if more is required, have the pot emptied of the old leaves, scalded, and fresh tea made in the usual manner.
Beetons Book of Household Management, 1861