The Buffet Blue Book by John H. Considine (1912, p.37)

1 piecelemon peel acid
1 wine glassIrish whiskey — Substituted for whiskey.base
1 lumpsugar base
hot water — Enough to dissolve sugar and fill the glass.dilution
nutmeg — Grate on top.other
  1. Prepare the drink in the same manner as Hot Whiskey Sling, substituting Irish whiskey for whiskey.
  2. Stir with a spoon, grate nutmeg on top, and serve.

Garnish: Lemon peel and grated nutmeg

Ice: None

This entry is explicitly substitution-based in the source.

The Up-to-Date Bartender's Guide by Harry Montague (1913, p.46)

1 slicelemon peel acid
1 jiggerIrish whiskey base
1 lumpsugar — Dissolved in the glass.base
hot water — Fill up.dilution
nutmeg — Sprinkled on top.other
  1. Dissolve the sugar in a hot whiskey glass.
  2. Add the Irish whiskey and fill up with hot water.
  3. Add the lemon peel, stir, sprinkle nutmeg on top, and serve.

Garnish: Lemon peel and nutmeg

See also: Hot Scotch Whiskey, Hot Irish Punch

Source says to prepare it the same as the above, substituting Irish whiskey instead.