Potato Bread Rolls

Boil, peel and mash the potatoes. Add in order the salt, the powdered milk

From 1916:

Potato bread contains more mineral matter, fiber and moisture, but otherwise, in composition and nutritive value, is practically the same as ordinary bread. Its higher moisture content helps to keep it fresh several days longer than ordinary bread, says Uncle Sam in his latest advice to housekeepers on cutting the cost of living.

Here is his tested recipe for break fast rolls:
Very good rolls can be made from a mixture of boiled potatoes and flour by adding shortening and sugar. The following proportions will yield one dozen small rolls:

Eight ounces of boiled and peeled potatoes, 6 ounces sifted flour, 1/3 cake of compressed yeast, ¾ level tablespoon salt, 2 tablespoons lukewarm water, 2 tablespoons sugar, 2 tablespoons butter.
Two tablespoons of powdered milk added to the dough will greatly improve the quality of the rolls. Although milk itself or cream may be used, it must be borne in mind that they will increase the liquid content.
Boil, peel and mash the potatoes. Add in order the salt, the powdered milk (if used), the yeast rubbed smooth and mixed with the water, and, lastly, two tablespoons of flour. Let this mixture stand at a temperature of about 86 degrees (Fahrenheit) until the dough begins to collapse.
Add to this sponge the butter, the sugar and the remainder of the flour and, if necessary, enough more flour to make a very stiff dough.
Knead thoroughly until a smooth dough, which is no longer sticky, has been formed. Set back to rise again, and when the dough has trebeled in volume knead lightly, form into small balls and place, not too close together, in greased pans. Allow to rise until double in volume and bake 20 minutes in moderately hot oven.