Arsmart or Water-pepper.
A COMMON wild herb, neglected, but of great virtues. It grows every where about ditches, and in watery places. It is a foot and a half high; the stalks are weak, green or reddish, and jointed. The leaves are long and narrow, like those of the peach tree, of a bright green, not spotted, and even at the edges. The flowers stand at the tops of the stalks in slender spikes, of a greenish white. As there are several other kinds of arsmart, and most of them different from this in their nature and qualities, great care is to be taken to gather the right. It must have no spot upon the middle of the leaf. There is another common kind of arsmart with such a spot, and with thicker stalks, and thick spikes of reddish flowers (probably Polygonum persicaria -Henriette), which has none of its virtue.
The right arsmart is an excellent medicine in obstructions of urine, in the gravel and stone: and in the jaundice and beginning of dropsies it has done great cures. The juice of the fresh gathered plant is the best way of giving it. Outwardly it is good to cleanse old ulcers.