THE Ult ART, OR AllROW-POISON OF THE INDIANS. 463 
The gentlemen who accompanied me on my expedition, 
and Senhor Pedro Ayres, a scientific person who had been 
sent by the commander of the district to welcome me at the 
Brazilian boundary, were present during these experiments, 
which established beyond doubt that the pure concentrated 
juice of the urari plant alone , without any assistance of Indian 
charlatanism or the addition of extraneous substances , proves fatal 
to animal life , if its juice, thus concentrated , be brought in contact 
with the blood . 
The boiling process was finished in less than seven hours, 
while the Indians employ more than forty-eight hours for 
that purpose; and as it required a period rather longer to 
produce death in the fowls wounded with it than would have 
been necessary with good urari, this must be ascribed to 
my decoction not being sufficiently concentrated. The poi- 
son which I had thus prepared, was of a yellow-browni-sh 
colour, — good Macusi poison is greenish-black, or even jet 
black; and I have no doubt that it receives this appearance 
from one of the ingredients which the Indians add to it. 
When I left Pirara, foiled in my purpose to see the poison 
prepared by the Macusi, I arranged with the late Rev. Thomas 
Youd, who laboured then as missionary of the Episcopalian 
church in that village, to try if he could induce this famed 
poison-maker to boil it in his presence, in which he fully 
succeeded, and he had the goodness to communicate the 
result to me in a letter, which is printed in extenso in my 
paper on the urari in the c Annals of Natural History/ 
vol. vii, p. 416. It is the most authentic document of the 
manner in which the poison is prepared, for I have since 
witnessed its manufacture myself. Snakes’ teeth, stinging 
ants, or any other animal matter, are not added to the mass. 
The urari bark alone is the ingredient which gives the active 
principle, and the other additions probably the consistence 
and colour. The herbs, the juice of which is added to the 
true urari bark, were, as far as I was able to ascertain their 
botanical character, Strychnos cogens , Benth., a species of 
Cissus , a plant belonging to the family of Xanthoxylacere , but 
the rest I could not recognise. The Cissus no doubt con- 
tributes to give consistence to the concoction. It deserves 
the passing remark, that all the ingredients which the Macusi 
use (excepting the Cissus,) for the preparation of their poison 
are of an intense bitter. 
The sagacity of the Macusi to try whether the poison he 
has prepared is of the strength he desires, by wounding a 
lizard, a cold-blooded animal, shows much more philosophy 
than as related by Father Gumilla, that an Indian wounds 
