The inquiry was hampered by the period of time that had elapsed since the deaths, and because doctors could not say what effect swabbing with spirits of salts would have. Suspicions were further aroused when it was shown that Rendell had purchased large quantities of spirits of salts during the period of the children's illnesses, but none since the last death. Armed with this information the detectives obtained permission to exhume the bodies and this was done on 3 July 1909. Police exhumed the bodies of the three children; diluted hydrochloric acid was found on the throat tissue.