Wash thoroughly half a peck of spinach, and put it dripping wet into a mortar; pound it into a pulp, and then place the pulp and juice in a strong cloth; twist the sides thereof tightly over, and then let two persons take a hold of each end and wring the juice out from the pulp in the same manner as you would wring out a sheet or any large cloth after washing it: a dish must be placed under the cloth to receive the juice as it is wrung out.
Next, pour the extract or spinach-juice into a small stewpan and set it over the fire; and, as soon as it curdles, scrape it out with a spoon upon a sieve in order to separate the water from the finished pulp; and a few minutes after it has drained, place it in a covered basin in a very cool place, to be used as hereafter indicated.