After being ingested, phosphide reacts with hydrochloric acid in the stomach, generating phosphine, a highly toxic gas. Purchase explained, "This dose was not sufficient to kill him outright, and its only effect was to so impair the functioning of the liver that he died a little time afterwards". When Purchase obtained Michael's body, it was identified as being in suitable condition for a man who would appear to have floated ashore several days after having died at sea by hypothermia and drowning.