This came from the files of Judy Bales, my late daughter-in-law. She loved keeping dessert recipes most of all and loved trying out new ones, especially to take to her school and share with the other teachers.
In a large bowl stir boiling water into gelatin for at least 2 minutes until completely dissolved. Stir in cold seltzer. Refrigerate 1-1/2 hours or until thickened (spoon drawn through leaves a definite impression).
Stir in oranges and strawberries. Spoon into a 6-cup mold.
Refrigerate 4 hours or until firm. Unmold on lettuce-lined platter. Store leftover gelatin mold in refrigerator.
NOTE: To unmold, dip mold in warm water for about 15 seconds. Gently pull gelatin from around edges with moist fingers. Shake gently to loosen. Place moistened serving plate on top of mold. Invert mold and plate; holding mold and plate together, shake slightly to loosen. Gently remove mold and center gelatin on plate.