Scrub the oranges and set them on the rack of an electric pressure cooker. Cover them with water, and soften them in the pressure cooker by cooking them for ten minutes. Let the pressure naturally release, and then rotate the oranges to promote even softening of their rinds, and then pressure cook them a further five minutes. If you don't have a pressure cooker, place the oranges in a heavy pot or Dutch oven, cover them with water and boil them for 2 ½ hours, rotating them to ensure even softening of their rinds. Reserve the oranges, and discard the water.
Allow the oranges to cool enough to handle them comfortably. Split them in half cross-wise, and nudge the seeds from their flesh using a butter knife. Discard the seeds. Scoop out the pulp from the orange halves, spoon it into the pitcher of a blender. Blend the orange pulp until smooth, and then pour the pulp into the pot.
Quarter the remaining orange rinds, then layer one piece on top of the other, and slice the rinds into matchsticks about ⅛-inch wide and 1-inch long. Drop them into the pot with the orange pulp.
Stir in the honey, and bring to a boil over medium-high heat. Turn down the heat to medium, and stir the marmalade constantly until set, 30 to 35 minutes. Take the marmalade off the heat, let it cool for five minutes, and then stir in the whiskey.
Spoon into clean jam jars, and process in a water bath for ten minutes.