170 Cc. J. MARTIN. 
cobra bite in the human subject the blood is however very 
frequently fluid, and non-coagulable. 
On other occasions, when taking carotid pressure tracings during 
the injection of larger doses of venom (0-0002 gramme per k 
or above this quantity), within a minute of the time when the 
poison was introduced, the record of the rise in pressure due to 
the heart’s beat disappeared, but the pressure in the manometer 
remained considerably aboye zero. On investigation it was found 
that there were no clots in or near the cannula, but in each cas? 
the artery, at some little distance from the cannula, contained ® 
solid core of clot extending into the aorta, and left ventricle. On — 
further dissection, the blood in the whole vascular system, except 
ing only the pulmonary veins and the left auricle, was found to 
be solid. The clot in the portal venous system was particularly = 
hard. These experiments I have repeated very many times, in : 
fact one or the other phase of coagulability occurs every time this . i 
snake poison is injected into a vein of a dog. ! 
Pseudechis venom is not the only kind of snake poison which 
influences the coagulability of blood-plasma. From the examine 
tion of the literature of snake poison in the light of knowledge 
gained from the above experiments, I felt convinced that some 
the results obtained by other observers working with different 
venoms, which results they attributed to quite other causes, ¥™ 
in reality due to intravascular clotting. Within the last : 
also, [ have had the opportunity of reading a paper by Heidens 
dealing with the same subject. This author found that Cro 
venom first raised the tendency of the blood to coagulate, 
that this increase was followed by a diminution in coagula 
He was of opinion that an excessive increase of coagulability ¢ 
occasion considerable thrombosis and the death of the 90” 
Heidenschild considers that the sudden death from large — 
venom which has been-observed by so many experimenters ¥° 
be explained in this way. : 
1 Untersuchungen iiber die Wirkung des Giftes der 
Brillen und def 
Klapperschlange—Inaug. Dissert. Dorpat 1886. ee 
