into a meeting place for about fifty students from all over the country. While receiving a thorough medical education they helped with the naturalistic studies of von Siebold. Expansion and politicization (1839–) The Rangaku movement became increasingly involved in Japan's political debate over foreign isolation, arguing that the imitating of Western culture would strengthen rather than harm Japan. The Rangaku increasingly disseminated contemporary Western innovations. In 1839, scholars of Western studies (called 蘭学者 "rangaku-sha") briefly suffered repression by the Edo shogunate in the incident, due to their opposition to the introduction of the death penalty against foreigners (other than Dutch) coming ashore, recently enacted by the Bakufu. The incident was provoked by actions such as the Morrison Incident, in which an unarmed American merchant ship was fired upon under the Edict to Repel Foreign Ships. The edict was eventually repealed in 1842. Rangaku ultimately became obsolete when Japan opened up during the last decades of the Tokugawa regime (1853–67). Students were sent abroad, and foreign employees (o-yatoi gaikokujin) came to Japan to teach and advise in large numbers, leading to an unprecedented and rapid modernization of the country. It is often argued that Rangaku kept Japan from being completely uninformed about the critical phase of Western scientific advancement during the 18th and 19th century, allowing Japan to build up the beginnings of a theoretical and technological scientific base. This openness could partly explain Japan's success in its radical and speedy modernization following the opening of the country to foreign trade in 1854. Types Medical sciences From around 1720, books on medical sciences were obtained from the Dutch, and then analyzed and translated into Japanese. Great debates occurred between the proponents of traditional Chinese medicine and those of the new Western learning, leading to waves of experiments and dissections. The accuracy of Western learning made a sensation among the population, and new publications such as the of 1759 and the of 1774 became references. The latter was a compilation made by several Japanese scholars, led by Sugita Genpaku, mostly based on the Dutch-language Ontleedkundige Tafelen of 1734, itself a translation of Anatomische Tabellen (1732) by the German author Johann Adam Kulmus. In 1804, Hanaoka Seishū performed the world's first general anaesthesia during surgery for breast cancer (mastectomy). The surgery involved combining Chinese herbal medicine and Western surgery techniques, 40 years before the better-known Western innovations of Long, Wells and Morton, with