The Bulletin 
65 
Cultures were made from livers, hearts, and kidneys of a total of six 
slieep and lambs and one hog dead of the disease, all of which cultures 
were negative. Cultures were made from the heart, liver and kidneys 
of a guinea pig dead of the disease, one of which cultures showed a 
growth, which organism later proved to be a contamination. 
Nature of the Poisonous Principle 
Since a relatively recent claim has been made (Moseley, 1909) that 
the feeding of aluminium phosphate is followed by effects similar to 
those following the feeding of white snakeroot, an attempt was made in 
1916 to produce trembles by feeding aluminium phosphate to sheep. 
Two ewes, 166 and 167, were accordingly maintained on this experi¬ 
ment from September 9 to November 17. During this time each ewe 
was fed 412 gm. of aluminium phosphate (A1 P0 4 ; Baker’s C. P.) 
mixed with 68.5 pounds of grain, this being supplemented with 138 
pounds of alfalfa hay. The daily amounts of aluminium phosphate 
given were gradually increased from 2 to 16 gm. 
At no time during this period of 69 days were these ewes observed 
to manifest any symptoms of trembles. The initial weight of ewe 166 
was 80 pounds, and her weight at the close of the experiment was 91 
pounds. The initial and final weights of ewe 167 were 90 and 93 
pounds, respectively. 
These results indicate that aluminium phosphate is not the active 
principle in white snakeroot and are in accord with statements more 
recently made by Moseley (1917). 
Certain of the experiments with sheep and guinea pigs which were 
made in 1917 indicate a number of points with reference to the nature 
of the active substance in the production of trembles and milksickness. 
No evidence has been obtained that it is water soluble, or alcohol solu¬ 
ble, and evidence of its solubility in dilute acid is inconclusive. With 
long desiccation at a temperature of about 100 degrees C., the substance 
seems to lose its toxicity. Such is not the case when the expressed juice 
is evaporated at about 60 degrees C. The plant furthermore contains 
a nontoxic volatile oil which does not pass into the milk; at least it 
has not been possible in the several attempts which have been made to 
distil it from milk from a cow fed on white snakeroot. There is fur¬ 
thermore present a considerable amount of resinous material which, 
according to a recent account by Moseley (1917), exists in the leaves to 
the extent of 9 per cent of their dry weight and is the poisonous princi¬ 
ple. This claim, however, is not supported by conclusive experimental 
data. 
