Preheat oven to 375. Sift together flour, 3/4 cup sugar and salt together 4 times into a bowl.
In separate bowl, beat whites with tartar until soft peaks form. add remaining sugar, 2 tablespoons at a time; beat well after each addition. Add extract.
Sift 1/4 cup flour mixture over whites; fold in gently. Fold in remaining flour mixture, 1/4 cup at a time. Pour batter into ungreased, 10" tube pan; bake 35-40 minutes. Turn pan upside down on wire rack and let cake cool in pan for 1 hour. The cake should come out of its own accord.