How was hemlock used to poison in ancient times?

In ancient times, small doses of the plant were used to relieve pain, with a great risk of poisoning. One species, Conium maculatum, was used to carry out the death sentence in ancient times. The Greek philosopher Socrates was condemned to death in 329 B.C.E. by drinking a potion made from hemlock. The hemlock plant was introduced to North America from Europe, and has often been mistaken for a pretty garden plant. All parts of the weedy hemlock plant are poisonous, especially leaves and seeds. Hemlock is a member of the wild carrot family, and it grows along roadsides and waterways in North America.