This section is from the book "Philadelphia Cook Book: A Manual Of Home Economies", by Sarah Tyson Heston Rorer. Also available from Amazon: Philadelphia Cook Book.
Whites of two eggs 1 teaspoonful of lemon juice 1/2 pound of powdered sugar
Place the eggs in a refrigerator or some very cold place one hour before using. Break them carefully and beat the whites until frotrhy, then sift the sugar in gradually, beating all the while; add the lemon juice, and continue the beating until the icing is fine and white, and stiff enough to stand alone. Keep in a cool place until wanted. Spread with a knife dipped in ice-water. If ornaments are used, they must be placed on the cake while the ice is still moist. This may be varied by adding different flavorings, such as strawberry, pineapple, rose, vanilla, etc.
Strawberry icing should always be colored with a few drops of cochineal.
1/4 pound of grated chocolate 1/4 pound of powdered sugar
Melt the chocolate over boiling water, add the sugar, and stir until smooth. Add a teaspoonful of vanilla, and it is ready to use.
1/2 pound of powdered sugar 1 tablespoonful of boiling water Grated rind of one orange Sufficient orange juice to moisten
Put the sugar in a bowl, add the rind and then the water and juice. The icing should be very stiff, and used immediately.
1 cup of granulated sugar White of one egg
1/4 teaspoonful of cream of tartar
1/2 cup of boiling water
Boil the sugar and water together until it spins a heavy-thread. Beat the egg to a stiff froth; add the cream of tartar, and then the syrup, beating all the while. Beat until cold and thick. Flavor.
Put one even tablespoonful of gelatine into a bowl, cover it with one tablespoonful of cold water, let it soak half an hour; then add two tablespoonfuls of boiling water, stir until dissolved, then add pulverized sugar to make the mixture a proper consistency to spread. Flavor to taste. Let the cake cool, spread the icing quickly over it, and stand in a cool place to dry.