Once she had dropped it, and the cork coming out, some of the contents had escaped.

Frightened at the mishap, she had filled the phial up with water, and put it, thus diluted, back on the shelf.

No one had noticed the difference, and she had forgotten all about the matter until now.
From her description, there must have been very little of the dangerous drug left in the phial; and the conclusions of Dr.Perry's autopsy received a confirmation which ended, after a mass of testimony tending rather to confuse than enlighten, the jury, in the non-committal verdict: Death by strangulation at the hands of some person unknown.
I had expected this.

The evidence, pointing as it did in two opposing directions, presented a problem which a coroner's jury could hardly be expected to solve.

What followed, showed that not only they but the police authorities as well, acknowledged the dilemma.