In August 1775, he arrived at the Dutch
factory of the V.O.C. at
Dejima, a small
artificial island (120 m by 75 m) in the Bay of
Nagasaki connected to the city by a single small bridge. However, like the Dutch merchants, Thunberg was at first rarely allowed to leave the island. These restrictions had been imposed by the Japanese
shogun Tokugawa Ieyasu in 1639 after the Portuguese, who had been the first Europeans to arrive in Japan in 1543, persisted in missionary activity. The only locals who were allowed regular contact with the Dutch were the interpreters of Nagasaki and the relevant authorities of the city. Shortly after the ''Schoonzicht's'' arrival on Deshima, Thunberg was appointed head surgeon of the trading post. To still be able to collect specimens of Japanese plants and animals as well as to gather information on the population, Thunberg began to construct networks with the interpreters by sending them small notes containing medical knowledge and receiving botanical knowledge or rare Japanese coins in return. Quickly, the news spread that a well-educated Dutch physician was in town who seemed to be able to help the local doctors cure
syphilis, known in Japan as the "Dutch disease". As a result, the appropriate authorities granted him more visits to the city and finally even allowed him one-day trips into the vicinity of Nagasaki, where Thunberg had the chance to collect specimens by himself. During his visits in town, Thunberg began to recruit students, mainly the Nagasaki interpreters and local physicians. He taught them new medical treatments, such as using mercury to treat syphilis, and the production of new medicines. During this process, he also instructed his pupils in the Dutch language and European manners, furthering the growing interest into Dutch and European culture by the Japanese, known as
rangaku. Thunberg had brought some seeds of European vegetables with him and showed the Japanese some botanical practices, expanding Japanese horticultural practices. Thunberg also profited from his teachings himself. As a former medical student he was mainly interested in medical knowledge, and the Japanese showed him the practice of
acupuncture. The exchange of ideas between Thunberg and the local physicians led to the development of a new acupuncture point called
shakutaku. The discovery of
shakutaku was a result of Thunberg's anatomic knowledge and the Japanese traditional medicine of neuronic
moxibustion. Thunberg brought back knowledge on Japan's religion and societal structure, boosting interest into Japan, an early cultural form of
Japonism. In both countries, Thunberg's knowledge exchange led to a cultural opening-up, which also manifested itself in the spread of universities and boarding schools which taught knowledge of the other culture. For this reason, Thunberg has been called "the most important eye witness of
Tokugawa Japan in the eighteenth century". Due to his scientific reputation, Thunberg was given the opportunity in 1776 to accompany the Dutch ambassador M. Feith to the shogun's court in
Edo, today's Tokyo. During that journey, he collected many specimens of plants and animals and talked to locals along the way. It is during this time that Thunberg started writing two of his scientific works, the
Flora Japonica (1784) and the
Fauna Japonica (1833). The latter was completed by the German traveller
Philipp Franz von Siebold, who visited Japan between 1823 and 1829 and based the
Fauna Japonica on Thunberg's notes which he carried with him all the time in Japan. On his way to Edo, Thunberg also obtained many Japanese coins, which he described in detail in the fourth volume of his travelogue,
Travels in Europe, Africa and Asia, performed between the Years 1770 and 1779. The coins provided new insights for European scholars into the culture, religion and history of Japan, as their possession and export by foreigners had been strictly forbidden by the shogun. This prohibition had been imposed to prevent the
Empire of China and other rivals of the shogunate from copying the money and flooding the Japanese markets with forged coins. In November 1776, after Thunberg had returned from the shogun's court, he left for
Java, now part of
Indonesia. From there, he travelled to
Ceylon (now Sri Lanka) in July 1777. Here again, his major interest lay in collecting plants and other specimens. In February 1778, Thunberg left Ceylon to return to Europe. ==Return to Europe==