Around the world sketching, collecting and sitting on moss

Joseph Dalton Hooker, confidant of Darwin, taxonomist, plant geographer, explorer, administrator and scientific panjandrum has never received the close attention he deserves. This magnificently illustrated and engagingly written book will surely help redress the balance.

Ray Desmond includes accounts of all Hooker's major travels: India, a circumnavigation of the Antarctic, the Atlas, Lebanon and finally the United States, quoting liberally from his letters. Hooker comes across as a person of strength and stamina, with a forceful, no-nonsense approach, opinionated but not rash, and interested in all manner of natural phenomena.

His trips were arduous and dangerous, such as James Clark Ross's Antarctic circumnavigation of 1839-43 when Hooker and his companions probed deep into the pack ice often in conditions of most extreme peril, before travelling four years later to the high altitudes of the Himalaya and the sodden vegetation of Khasia and Shillong. Sometimes patience was all that was required, as when he sat on frozen tufts of mosses and lichens in Kerguelen's Land until they thawed. A far cry indeed from the seven-year-old boy his mother described as "extremely industrious, though not very clever" and "croaky Joe" because of a persistent cough.

Hooker was a good artist in his own right, and Desmond includes many of Hooker's field sketches, sometimes with colours indicated. In Hooker's books and articles, these sketches were the bases for lithographs drawn by the talented and incredibly prolific Walter Fitch, long associated with Hooker. Several examples show us both the original and the final lithograph, and sometimes an intermediate watercolour or sepia drawing by Fitch. Fitch generally seems to have interpreted Hooker's intentions quite faithfully, but a question that is not answered is when Hooker added the colours, for instance to a sketch made under atrocious conditions in the Donkia pass. In Fitch's interpretation of this sketch, these colours are toned down considerably, and one wonders what influence the romantic artist Salvator Rosa, whom Hooker clearly admired and who Desmond mentions twice, might have had on Hooker's landscapes.

Desmond allows us to feel the tensions underlying 19th-century exploration, beyond those associated with organising what at times amounted to almost a small army of collectors, porters and assistants. Hooker recorded the natural habitat, yet at the same time was an agent in its change. Goats had largely destroyed the vegetation on Trindade island, off Brazil, but Hooker's group still left behind a cock and two hens. Hooker noted the depredations of collectors in the Khasia Hills. He saw hundreds of baskets with flowers being removed to Calcutta Botanic Gardens, yet he himself collected seven man-loads of Vanda coerulea for Kew (most died, yet for a private individual collecting live plants could be extremely lucrative). There were problems with money. Even as a member of the Royal Navy and on an official expedition, Hooker (and his parents) had to buy basic books and equipment that made his collecting during the Antarctic voyage possible; the Indian trip cost them £1,000.

There were problems over ownership of what had been collected and over intellectual property rights. But, above all, Hooker's explorations were intimately connected with Britain's imperial ambitions and needs. In India, he visited warehouses full of opium, Britain's main export to China. Archibald Campbell, Hooker's travelling companion in Sikkim and political agent there, was temporarily imprisoned by the rajah of Sikkim. The result was a punitive expedition by the British and the annexation of some of his country. Hooker's map of Sikkim was the basis of one prepared by the Indian Trigonometric Survey and was used subsequently for boundary demarcations.

Desmond is to be congratulated on producing an accessible book that is visually stunning and a contribution to our knowledge of 19th-century natural history and exploration. In 1849, Hooker wrote to his father: "It is impossible to begin observing too soon, or to observe too much." Much labour and skill were involved in this process of observation, and this book, with hundreds of Hooker's sketches and Fitch's lithographs, is a memorial both to Hooker's powers of observation and to his collaboration with Fitch.

P. F. Stevens is professor of biology, University of Missouri, St Louis, and curator, Missouri Botanical Garden.