36                                       Surra.

of bright yellow color and of heavier specific gravity than
the second which is of a brownish tinge.

Dr. Hankin kindly analysed these specimens and informed
me that the first contains 72 % of a substance soluble in
dilute hydrochloric acid. This soluble substance consisted
chiefly or entirely of white arsenic.

No. 2 contains 2.6 % of substance soluble in dilute hydro-
chloric acid.

In our experiments we found that the second sample of
orpiment was of no use in the treatment of Surra and in
small doses caused colic.