POISON SUMACH. 405 
those who are constitutionally liable to it. On the 
27th of October, 1814, Dr. A. L. Pierson, then a 
student of medicine, accompanied me to Brighton 
for the purpose of collecting the juice of the Rhus 
vernix, growing at that place. He had always 
supposed himself constitutionally exempt from 
liability to the poison. The day preved warm, 
and the efflavium from the incisions we had made 
in the trees was very powerful. We were engag- 
ed in the collection for upwards of an hour, dur- 
ing which he was less exposed than myself, be- 
ing absent a part of the time. His own account 
of the symptoms which followed this exposure is 
as follows: } 
“J felt no unpleasant effects for six or seven 
hours after returning to Boston. About 8 o’clock 
P. M. I perceived the backs of my hands were 
swollen and puffy, but without pain or itching; — 
my forehead and upper lip Were soon in the same. 
state. On the morning of the 28th the tumefac- 
tion had increased, and I discovered various other 
parts of my body to be infected. ‘The backs of my 
hands and wrists, which were the most advanced, 
began to show small watery vesicles. No appli- 
cations were made till the noon of this day. I 
then applied cloths dipped in lead water to one 
hand and wrist, and in a spirituous solution ofthe 
14 
