Cook orange rinds in boiling water until tender; drain.
With a spoon scoop out and discard the white portion, then finely chop outer peel.
Sprinkle or crumble yeast into the 1/4 cup warm water, and stir until dissolved.
Using a large mixing bowl, mix together orange peels, the lukewarm water, molasses, sugar, salt, dissolved yeast, and shortening.
Sift flours, measure, and sift again; gradually add them, and beat until smooth.
Knead lightly and let rise until almost doubled in bulk.
Shape into 2 loaves and place in 9 by 5-inch loaf pans.
Let rise until almost doubled in size.
Bake in a moderately hot oven (375°) for 40 minutes.