RHUS TOXICODENDRON. ORD. XXXVIL. Dumose. hee 
broken off, a yellowish milky juice immediately exudes from the wounded 
extremity ; after a short exposure to the air, it becomes of a black colour, 
and does not again change. This juice, applied to linen, forms one of the most 
perfect kinds of indelible ink; it does not fade from age, washing, or 
exposure to common chemical agents. I have repeatedly, when in the 
country, marked my wristband with spots of this juice; the stain was at 
first faint, and hardly perceptible, but in fifteen minutes became black, and 
was never afterwards eradicated by washing, but continued to grow darker 
as long as the linen lasted.”* 
Poisonous Effects. An acrid poison exists in the juice of the Toxicodendron, 
and in many other species of the Rhus genus.+ The symptoms commonly 
produced are violent itching, redness, tumefaction of the face and other parts 
affected; succeeded by vesications, great swelling, heat, pain, and fever.{ 
The symptoms often begin in a few hours after the exposure, and when the 
disease is at its height, the skin becomes covered with a crust, and the 
swelling is so great, as in some instances to close the eyes, and almost to 
obliterate the features of the face. The celebrated Fontana relates, that 
having touched at three different times, and at the interval of several days, 
some leaves of the Toxicodendron, he experienced some serious symptoms : 
some days after, the eye-lids, the extremities of the ears, and almost every 
part of the face became tumefied, and filled with an aqueous fluid; the 
spaces which separate the fingers, became red, and were covered with small 
vesicles, full of transparent humour; the epidermis came off in little scales, 
and he felt a terrible smarting for the space of a fortnight, and an insup- 
portable itching for a longer period. The disease produced by this poison 
requires the general antiphlogistic treatment, viz. rest, low diet and evacua- 
tions: if the symptoms be very violent, bleeding may be occasionally re- 
quired, and the usual means resorted to in erysipelatous disorders. 
Medical Properties and Uses. The leaves of this plant are narcotic, stimu- 
lant, and somewhat aperient. It appears to have been introduced into prac- 
* Some attempts have been made with a view to ascertain the nature of this colour- 
ing principle, and the means of fixing it on stuffs, but without success; the reason of 
this appears to be that the colouring principle does not reside in the sap, but in a pecn- 
liar secretion or suceus proprius of the plant, and is wholly insoluble in water: hence, 
some other medium becomes necessary for its solution. 
+ Viz. Rhus pumilum, R. typhinum, R. vernix, &e. 
+t This disease appears to be of an erysipelatous nature.—Ep. 
