Having previously embarked on a collecting expedition to the Pyrenees, backed by Sir William Hooker and George Bentham, the botanist Richard Spruce (1817–93) travelled in 1849 to South America, where he carried out unprecedented exploration among the diverse flora across the northern part of the continent. After his death, Spruce's writings on fifteen fruitful years of discovery were edited as a labour of love by fellow naturalist Alfred Russel Wallace (1823–1913), whom Spruce had met in Santarém. This two-volume work, first published in 1908, includes many of the author's exquisite illustrations. Showing the determination to reach plants in almost inaccessible areas, Spruce collected hundreds of species, many with medicinal properties, notably the quinine-yielding cinchona tree, as well as the datura and coca plants. Volume 1 contains Wallace's biographical introduction and a list of Spruce's published works. The narrative includes discussion of Pará, Santarém, and the Negro and Orinoco rivers.