Sift together potato flour, cake meal and salt. Beat eggs until light. Add 1/2 cup water and beat again. Gradually add 1 cup water to the dry ingredients, stirring until smooth. Add beaten eggs to batter, a small amount at a time, stirring each time until smooth.
Grease a 6-inch skillet lightly with a piece of buttered waxed paper. Place over a moderately-high flame (#2 on an electric stove) . Fill a cup with batter. When the skillet is hot, pour about 1/2 cup batter into the skillet . As soon as the batter clings to the bottom of the skillet (if your skillet is at the right temperature, this will be almost immediately). Pour the excess batter back into the cup. When the blintz "blisters" and the edges curl away from the sides of the skillet, invert the skillet over a wooden board (cloth covered) and the blinmtz will fall out. (it may be necessary to tap the edge of the skillet against the board) The batter should be stirred again before frying each blintz. Grease the skillet about every third frying. (See cheese fillling above, or create your own filling.)