This section is from the book "The National Cook Book", by A Lady Of Philadelphia. Also available from Amazon: I Know How to Cook.
Select the lightest colored oranges for this purpose, as they are more acid than the dark. Peel off the rind and slice them, latitudinally or crosswise, about the eighth of an inch in thickness. Strew over them some powdered white sugar, in the proportion of a tea spoonful of sugar to each slice. Let them stand fifteen minutes. They are very palatable in fevers, as they serve to cleanse the mouth and keep it cool.
These may be prepared in the same manner as the sugared oranges (see above,) only they should have a tea spoonful and a half of sugar to each slice; as they are more firm than oranges, they require to stand longer to become perfectly impregnated with the sugar.
They are better to stand about an hour before they are to be eaten. The white skin should be carefully peeled off, as it imparts an unpleasant bitter flavor when permitted to remain long in the sugar. These are very grateful to the sick and feverish.
Select fine large lemons. Peel off the outer skin and as much as possible of the white skin. Cut them in slices latitudinally or round the lemon, about the eight of an inch thick. Sprinkle them with white powdered sugar, a tea spoonful of sugar to each slice. Let them stand three hours, then strain off as much of the juice as possible from the lemons, put it in a sauce-pan over a slow fire, and as soon as the juice begins to simmer throw in the slices of lemon. Let them cook five minutes, take them out and pour the syrup over them. Should the lemons not prove sufficiently juicy to melt the sugar entirely, a little water may be added.
 
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