Little is written in textbooks of medical history about Nansen, who is better known as the Norwegian who founded modern polar exploration. His contributions were in many spheres. Nansen was an invertebrate zoologist who in 1882 was appointed curator of zoology at the Bergen museum. He stayed in Bergen for 5 years, focusing his interests on the neuroanatomy of marine invertebrates. For one of his papers “The structure and combination of histological elements of the central nervous system” (1887), the university in Kristiana conferred upon him the degree of doc- tor of philosophy. His dissertation contained so many novel interpretations that the examination committee accepted it with reluctance, but the work is now considered a classic. Two days after his dissertation was accepted Nansen was on his way to Greenland. He crossed Greenland on skis during 1888–1889. Nansen was appointed professor of zoology at the University of Oslo in 1887 and in oceanography in 1908. On the basis of his research on the nervous system of an obscure marine invertebrate, the myzostome, he first expressed doubt about the reticular nature of nervous structure. In 1886 he visited Camillo Golgi at the University of Pavia and learnt Golgi’s new method of staining nerve cells. Nansen was preoccupied with the question of how nerves communicate with each other and was a pioneer advocate of what later became known as the neurone doctrine. He was quite adamant that nerve units were not fused, but only touched each other. Nansen, His, and Forel, working from different points of view, had sown the seeds of doubt about the reticular theory and became cofounders of the modern view of the nervous system. Ramon Y Cajal’s declaration of the independence of the nervous cellular unit was published in May 1888, a year after Nansen’s original paper. Nansen also offered an explanation of the reflex arc, proposing that sensory nerves conduct information from the periphery, and central cells relay the impulses to motor nerves, which activate muscles. He discovered that spinal ganglia bifurcate into ascending and descending processes, and was the first to postulate the ectodermal origin of Schwann cells. Nansen also described Leydig’s “dotted

substance”, now called the neuropil, and showed that the nerve fibres in the dotted substance were in contact, but did not anastomose with each other. By 1906, when Raymon Y Cajal and Golgi were sharing the Nobel Prize in physiology or medicine, Nansen was Norwegian ambassador in London. He had become famous for his exploration of the Arctic, and had played a key part in the dissolution of the union between Sweden and Norway. His endeavours were probably decisive in avoiding war and ensuring peaceful collaboration between Norway and Sweden. Later, he made major contributions to the foundation of the science of physical oceanography, and after the First World War worked extensively with the repatriation of prisoners of war and refugees, and with famine relief. For his humanitarian efforts he was awarded the Nobel Peace Prize in 1922. He is shown here in one of his several philatelic honourings on a

stamp from Norway with Roald Amundsen, the Norwegian explorer who was first to reach the South Pole on December 14 1911, 33 days before Scott (Stanley Gibbons no 392, Scott no 287). When Amundsen left Norway he sailed in Nansen’s old ship Fram (Norwegian for Forward), which is also shown. Fram was a unique vessel designed for Nansen to resist the extreme pressures of pack ice in the polar regions. Amundsen had studied medicine for period but withdrew to go to sea.