From 1922:
A tempting morsel for a very hot day: Soak a third of a box of gelatine in a third of a cupful of cold water, then add a third of a cupful of boiling water. Stir in 1 cupful sugar, 1 cupful uncooked fruit ; pulp cut into small pieces and mixed, juice of 1 lemon. Set in a pan of ice water and stir slowly until it begins to thicken; then pour into small cups, bottoms garnished with blanched peach-meats and bits of candied fruits. Chill on ice or in cellar until firm. When ready to serve dip each cup into hot water an instant, and invert on to lettuce cups. Serve one to each guest, pouring a tablespoonful of sauce over each.
For the sauce put 1 pint of orange or pineapple juice to heat, add sugar to suit taste, juice of half a lemon, half an even tablespoonful of arrowroot moistened with cold water. Stir until smooth and transparent. Serve everything quite cold.