To judge of an oven’s heat, try the oven every ten minutes with a piece
of white paper. If too hot, the paper will blaze up or blacken. When
the paper becomes dark brown, darker than ordinary meat, pie crust,
the oven is fit for small pastry. When light brown, the color of nice
pastry, it is ready for tarts. When the paper turns dark yellow you can
bake bread, large meat pies, or pound cakes. If it is just tinged, the
oven is fit for sponge cake and meringue.