SWEET ORANGE JAM

Cut oranges in as thin slices as possible, picking out all the pips

From 1922:

Cut oranges in as thin slices as possible, picking out all the pips; put the cut up oranges in a basin, and add 1 pint of water to each orange; put pips in another dish, cover with some of the water. Let these both stand all night, then strain the water off pips, and add it to the oranges; boil till skin and pulp are quite soft, let stand another night, then add weight for weight of sugar, and boil briskly till it jellies.