Rhubarb Meringue Pie

3 c. rhubarb
Baked pie crust
1 1/2 c. sugar
3 egg whites
3 egg yolks
6 T. sugar
2 to 3 T. butter
1/3 tsp. cream of tartar
3 T. flour

Mix thoroughly in large saucepan the rhubarb, sugar (1 1/2 c.) egg yolks, butter, flour. Place over low flame until juice appears, then increase heat until it starts to boil. Stir it while doing this. Reduce heat; cook until thick. Watch closely, as it scorches easily. Put into baked pie crust. Cover with meringue made with egg whites, cream of tartar, and (6 T.) sugar. Bake in quick moderate oven until meringue is golden brown.