Grate rind of oranges into bowl.
Add sugar and citric acid and pour boiling water over all, stirring to dissolve sugar.
Squeeze oranges and lemons and add juice to cooled mixture.
Let stand 24 hours.
Strain and bottle.
Keep in refrigerator.
For each 8-oz.
glass of orangeade use 1/3 to 1/2 cup syrup and fill glass with ice and water.