Put 4 cups of water and the sugar in a saucepan over medium-high heat.
Stir to dissolve the sugar. When the mixture comes to a boil, remove from heat
Add the teabags and allow to steep about 2 hours
Pour the tea into a one-gallon pitcher
Add rum and lemon slices, top up with cold water to fill and stir
Put in the fridge to chill for several hours or overnight
Serve over ice in glasses
Notes
This drink is not overly sweet. Add more (or less) sugar depending on your preferenceSteep the tea for a shorter or longer time for a weaker or stronger tea.Add ice to glasses, and not to the pitcher, to avoid watering the drink down.Tip: Brew extra tea to freeze in ice cube trays. Use in place of ice and your drink won't be watered down.