Weights and measures were different in the 17th century, for example barley cou
ld be sold in pecks or in pints, and with small quantities such as medicines the basis for an apothecary was the system of the "grain". Weights were as follows:One grain
One scruple = 20 grains
One drachm = 60 grains
One ounce = 480 grains
One pound = 12 ounces = 5760 grains
The only liquid measure in the Apothecary System was the liquid grain which was the volume of water weighing one grain, but this was not introduced until much later in 1885. (The picture above shows a 17th century set of weights.)
As a novelist, although I might have wanted to use the term "scruple" for Geofrey Fisk to measure his medicine I chose not to, as "scruple" in modern usage has quite a different meaning.
Until the 20th century lady's slipper root - sometimes called moccasin flower - was used by Native Americans as a nervine and sedative, but modern pharmaceuticals with less side effects have replaced it today.
In Britain there have only been three deaths over the last fifty years that might have been caused by plants, but that does not mean you should not be wary of certain flowers and berries.
Hemlock is the most notorious killer, which causes paralysis of the lungs if ingested. In the Middle Ages a general anaesthetic was made out of hemlock, henbane and opium and used before surgery, particularly during amputations. Hardly surprisingly this kept the patient in a deep sleep for several days until the antidote was administered - vinegar!
Another poison, Deadly Nightshade or Belladonna, was used in the 17th century to increase a woman's attractiveness by dilating the pupils. It was dropped into the eyes, and caused blurred vision. If you were to drink it however you would suffer from convulsions, coma and finally death.

More information about poisonous plants from www.thepoisongarden.co.uk
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