62 
MERCURIAL OINTMENT AND VAPOR OF MERCURY. 
containing mercury soon becomes white, in consequence of the 
evaporation of the latter. If a thin animal membrane be inserted 
between the two, the amalgamation ought to continue if the mem- 
brane allowed the vapors of mercury to permeate it. A glass ves- 
sel containing mercury was tied over with a piece of peritoneum, 
the external surface of the latter coated with leaf-gold, and the 
whole placed in a warm place. In three weeks the gold had not 
become amalgamated, nor did it become so when the mercury was 
heated to ebullition, and the internal surface of the peritoneal mem- 
brane was coated with globules of mercury. 
This experiment shows, that mercury does not penetrate animal 
membranes even in the gaseous state ; hence it cannot be taken up 
in the living body. Some experiments made upon rabbits render 
it probable that the vapor of mercury, when inspired, condenses 
within the organs of respiration, there becoming oxidated by inti- 
mate contact with the air and gradually absorbed. 
1. A rabbit was exposed in a capacious box during an hour to 
the vapor of boiling mercury. When it was taken out, it crawled 
with difficulty, and its breathing was very quick, but in the course 
of the day it recovered itself. The next morning it appeared to be 
in a very great state of uneasiness. It was again exposed to the 
vapor of mercury for an hour and a half. Soon afterwards it was 
seized with tetanic spasms, and died at the third seizure. On dis- 
section, the mucous membrane of the trachea and bronchi was found 
strongly injected, and the bronchi mucous contained globules of 
mercury. In the lungs, numerous spots of hyperaemia were foundj 
they varied in size from that of a lentil to a pin's head ; also seve- 
ral larger red and gray spots, between which the substance of the 
lung was in a state of hepatization. By the aid of a lens and the 
microscope, the nuclei of several of these hyperaBmic and hepatized 
portions were seen to be formed by globules of mercury. This 
experiment, when repeated several times, always gave the same re- 
sult. 
2. A rabbit was exposed for half an hour to the vapor of mer- 
cury. In the course of the day it seemed very dull, did not eat, 
breathed quickly, and was in a constant tremble ; on the following 
day it was active, and remained so until the fourth day, when it 
was killed. The bronchial mucous membrane was unchanged ; 
