Acidulated Raspberry Syrup

From 1894:

Put 6 lb. of raspberries into a china or glass bowl with a quart of water, in which has been dissolved 2 ½ oz. of tartaric (or preferably citric acid), and let it remain twenty-four hours; then strain it, taking care not to bruise the fruit. To each pint of clear liquid add 1 ½ lb. of pounded loaf sugar, and stir it with a silver spoon till dissolved; leave it for a few days, and then bottle it close. A little of this syrup with water forms a most refreshing drink in warm weather, and is of use in some febrile disorders. Strawberry syrup can be made in the same way, using 2 oz. of citric acid instead of 2 ½ oz. of tartaric acid.