This is a heritage recipe that I used to make about 50 years ago. Watch out for the measurements for the eggs. Large eggs used to be much larger then so use the cup measure. You will probably need an extra egg. Back in the 1970's when there were not enough large eggs to fill the demand, they changed the requirement for egg size. What we get now that are called "large", we used to call "medium". Watch out for this when you prepare heritage recipes.
1Have ready an ungreased 10 inch tube pan. Set oven to 375 degrees F. Sift flour before measuring.
2Measure sifted flour, baking powder, salt and 1 cup of sugar into a sifter and sift into a small mixing bowl.
3Combine egg whiles and cream of tartar in a large mixing bowl. Beat until soft mounds begin to form. Then add remaining 1/2 c. of sugar gradually, by sprinkling 2 tbsp at a time over whites and continue beating until stiff peaks form. Do not underbeat.
4Combine yolks, water and flavourings. Add to sifted dry ingredients and beat for 1/2 minute.
5Fold egg yolk mixture carefully into beaten egg whites until blended - about 40 folding strokes. (Do not stir or beat.)
6Pour batter into pan. Cut gently though batter to remove large air bubbles.
7Bake in moderate oven, 375 degrees F for about 35 minutes.
Cool cake in pan upside down for 1 to 2 hours. Then gently loosen the cake from the sides and center tube of the pan with a knife and gently pull out the cake.
8Serve plain or top with whipped cream and berries to garnish.