Pick the grapes from the stems, wash and drain them. Mash them with a spoon. Put them in the preserving kettle, and cover them closely with a large plate. Boil them ten minutes. Then pour them into your jelly bag, and squeeze out the juice.
Allow a pint of juice to a pound of sugar. Put the sugar and juice into your kettle, and boil them twenty minutes, skimming them well.
Fill your glasses while the jelly is warm, and tie them up with brandy papers.