Dig up sweet flag roots [Acorus calamus]* in May, wash, and toss them immediately into cold water. Soak them for 3 days, each day changing the water. Peel the roots with a knife and again soak in water overnight. The next day bring the roots to a boil in 2 waters [i.e., change the water once and bring the second water also to a boil]. Use a large kettle, because the more water, the sooner the bitterness will be boiled out of the roots. Each time after boiling the roots, toss them into cold water. After bringing the water to a boil the second time, soak the roots in cold water until the next day, changing the water several times. Finally, cut the sweet flag into pieces, cover with water, and keep changing the water until the roots are no longer bitter. Lay out the sweet flag on a napkin, cover with another napkin, pass a rolling pin over the roots, and press down firmly to squeeze out all the moisture. For 1 lb sweet flag, weigh out 2 lbs sugar and 1 glass water. Bring the syrup to a boil, cool, and add the sweet flag. Cook over a low fire, stirring with a spatula and removing the pan frequently from the fire so that the bottom does not burn. When the syrup has thickened enough so that it begins to coat the spoon, turn the sweet flag out onto a platter and sprinkle with sugar. To hasten the drying process, keep the platter in front of the fire. Then pack into a jar.
Another way: Peel the roots, cut into pieces, and drop them into cold water for 4 hours. Remove from the water, cover with milk, and cook for a long time. Plunge them into cold water for another 5 minutes and cook in fresh milk until tender. Rinse them thoroughly, place in a napkin, cover with another, and pass a rolling pin over to press out all the moisture. For 1 lb sweet flag, weigh out 2 lbs sugar and 1 glass water. Proceed further as indicated above.