Scotch Orange Chip Marmalade

Take equal weight of fine loaf sugar and Seville oranges. Wipe and grate the oranges but not too much. (The grate boiled up with sugar will make an excellent conserve for rice, custard or batter puddings.) Cut the oranges the cross way, and squeeze out the juice through a small sieve. Scrape off the pulp from the inner skins, and pick out the seeds. Boil the skins till perfectly tender, changing the water to take off part of the bitter. When cool, scrape the coarse white thready part from the skins, and trussing three or four skins together for despatch, cut them into narrow chips. Clarify the sugar, and put the chips, pulp, and juice to it. Add, when boiled for ten minutes, the juice and grate of two lemons to every dozen of oranges. Skim and boil for twenty minutes; pot and cover when cold.