A solution (not officinal) containing a double iodide of arsenic and mercury, has long been in use under the name of its proposer - Mr. Donovan, of Dublin (1839). It is a pale-greenish colored liquid, having no odor, but a styptic taste; it probably contains the red iodide of mercury and ter-iodide of arsenic. In each fluid drachm there is about 1/12 gr. arsenic, 1/4 gr. mercury, 3/4 gr. iodine.