In 1802 President Thomas Jefferson wrote to Dr. Benjamin Rush, a Philadelphia physician, asking him to prepare some questions to serve as guidelines for an exploration of the Missouri River and the river that would lead from the Missouri's source westward to the Pacific. [Nebraska History, Summer 1970]
In Philadelphia Meriwether Lewis, chosen by Jefferson to lead the expedition to the Pacific, was to obtain supplies and meet Dr. Rush, who gave him "Directions" for preserving the health of the party. They included:
1. When you feel the least indisposition, do not attempt to over come it by labour or marching. Rest in a horizontal posture, also fasting and diluting drinks for a day or two will generally prevent an attack of fever. To these preventives of disease may be added a gentle sweat obtained by warm drinks, or gently opening bowels by means of one, two, or more of the purging pills.
2. Unusual costiveness is often a sign of approaching disease. When you feel it take one or more of the purging pills.
3. Want of appetite is likewise a sign of approaching indisposition. It should be obviated by the same remedy.
4. In difficult & laborious enterprises & marches, eating sparingly will enable you to bear them with less fatigue & less danger to your health.
5. Flannel should be worn constantly next to the skin especially in wet weather.
6. The less spirit you use the better. After being wetted or fatigued, or long exposed to the night air, it should be taken in an undiluted state. 3 tablespoons taken in this way will be more useful in preventing sickness, than half a pint mixed with water.
Dr. Rush also provided the expedition with his famous bilious pills; fifty dozen were carried on the journey.