Memoranda on Poisons

"[...]above its local influences in relieving pain, &c. Various narcotic poisons produce but little local change, though their remote effects are very remarkable. For example, belladonna, in whatever way it may be introduced into the system, paralyzes the ciliary nerves and so causes dilatation of the pupil. Many substances have both a local and remote action, as is well seen in the influence of cantharides upon the part to which they are applied, and their remote effects upon the urinary organs. These remote effects must be induced by one of two modes, or, as some contend, by both: by absorption, that is, by the passage of the poisonous particles into the blood; or by sympathy, that is, by an impression transmitted [...]".