Note 60 — Chapter XXIII
Reading edition
The leaves of this shrub (Erythroxylon coca) contain a stimulant substance that in its effects is much like the active principle of coffee. They are much used by the native laborers to ward off the feeling of lassitude that comes with severe labor in a tropical climate. A native porter will carry a load of one hundred pounds a distance of sixty miles with no food or rest, but merely chewing a few coca-leaves. The plant yields the substance cocaine, now in demand all over the world as an anæsthetic in eye and throat surgery.