Another way.
Stone and split the fruit without taking off the skin. Weigh an equal quantity of sugar and fruit, and strew part of the sugar over the greengages, having first laid them on dishes, with the hollow part uppermost. Take the kernels from the stones, peel and blanch them. The next day, pour off the syrup from the fruit, and boil it very gently with the other sugar eight minutes. Skim it, and add the fruit and kernels. Simmer the whole till quite clear, taking off any scum that rises. Put the fruit, one by one, into small pots, and pour the syrup and kernels to it.