“ ‘This solution deposits in a few hours the greater part of the strychnine salt as an insoluble bromide in transparent crystals. A lady in England lost her life by taking a similar mixture: the precipitated strychnine collected at the bottom, and in taking the last dose she swallowed nearly all of it!’

“Now there was, of course, no bromide in Dr. Wilkins’ prescription, but you will remember that I mentioned an empty box of bromide powders. One or two of those powders introduced into the full bottle of medicine would effectually precipitate the strychnine, as the book describes, and cause it to be taken in the last dose. You will learn later that the person who usually poured out Mrs. Inglethorp’s medicine was always extremely careful not to shake the bottle, but to leave the sediment at the bottom of it undisturbed.