A common little plant upon our heaths, and in dry pastures, with numerous leaves and blue or white flowers, (for this is a variety and caused by accidents) disposed in loose spikes. The root is long, and divided into several parts, the stalks are very numerous, and very much branched, they are slender and weak, and they spread themselves upon the ground, forming a little green tuft. There is great variety in the appearance of the plant, beside what has been already named in the colour of the flower; nor is that indeed the only variation there: so that it has been divided into two or three kinds by some writers, but as all these will rise from the same seed, and only are owing to the soil and exposure, the plant is without doubt the same in every appearance, and its virtues are the same in which ever state it is taken. When it grows in barren places, the stalks are not more than three or four inches in length, and the leaves are very numerous, short, and of an oval figure. The flowers are in this case small and blue, sometimes whitish, striated with blue, and sometimes intirely white. When the plant grows in somewhat more favourable soil, the leaves are oblong, and narrow, pointed at the ends, and of a beautiful green, the stalks are five or six inches long, and the flowers in this case are commonly blue, and this is the most ordinary state of the plant. When it grows in very favourable places, as upon the damp side of a hill, where there are springs, and among the tall grass, then its leaves are longer, its stalks more robust and more upright, and its flowers are red. These are the several appearances of this little plant, and it is all one in which of them it is taken. The root is often of a considerable thickness, and single, but it is more usually divided and smaller; it is whitish, and of a disagreeable acrid taste.
This plant had passed unregarded as to any medicinal use, till Dr. Tennant brought into England the senekka root, famous in America against the effects of the bite of the rattle-snake, and found here to be of service in pleurisies: but when it was found, that this was the root of a kind of milkwort, not very different from our own, we tried the roots of our own kind, and found them effectual in the same cases: as to the poisonous bites of a serpent, they are so uncommon here, that we need not regard that part of the qualities, but we find it good in the other disorder, and in all diseases in which the blood is thick and sizy. The fresh root is best, but it has not its full virtue except in spring, when the stalks are just shooting out of the ground, for this reason it is most proper to take it up at that time, and dry it for the service of the year. When fresh, it is best given in infusion: but when dried, it is kept in powder.