I found this recipe in an old cookbook I have and made a double batch today. They are delicious. My recipe tweaks are in ().

Oatmeal Drop Cookies, The Modern Family Cookbook by Meta Given, 1942

1-1/2 cups all-purpose flour

1/4 teaspoon salt

1 teaspoon baking soda

1 teaspoon cinnamon

1/2 cup shortening (I used unsalted butter)

1 cup sugar

1 egg

1-1/2 cups old-fashioned rolled oats

2/3 cup buttermilk

1/2 cup chopped walnuts

1 cup plumped raisins (I used green seedless raisins plumped in brandy)

(I also added 1 teaspoon of vanilla)

Sift flour, measure, and resift twice with salt, soda, and cinnamon. Cream shortening, blend in sugar, and add slightly beaten egg, beat until smooth and light. Stir in half the flour, then add buttermilk, the rest of the flour, oats, nuts, and raisins, stirring until mixed. Drop from a teaspoon onto buttered baking sheet (I used parchment), and bake at 400 degrees for 10 minutes. (I used a tablespoon and baked for about 13 minutes.)

(I found the dough to be too soupy when I first mixed it so I added a 1/4 teaspoon baking powder, a 1/4 cup oats, and a 1/4 cup flour. I suspect that using the powdered buttermilk instead of the real thing and butter instead of shortening had this effect. Refrigerating may have solved the problem but I didn't have time.)