Recently I came across a portrait of Heinrich Bürger made when, as a secretary to Philipp Franz von Siebold, he visited Edo (now Tokyo) in 1826. This portrait is a rough sketch, and so far probably is the only portrait of him in existence. It was made by Watanabe-Kwazan (written also as Kwazan Watanabe after the western manner), an eminent artist, who, at that time, was also highly distinguished as a scholar of western thinking, a consequence of his Dutch learning. The present sketch was found in a collection of Watanabe's works owned by an old family, Kasuya by name, residing in the town of Kira in Aichi Prefecture. Watanabe's last place, Tabara, is located south of Kira beyond the Bay of Mikawa. Watanabe died there in 1841. Burger's biographic data remained practically unknown until 1962, when his life (he was born in or around 1806 and died in 1858) and work were brought to light by Mrs. M. J. van Steenis-Kruseman (1962). Before Mrs. van Steenis's paper was published, all that we knew about Bürger was that he had served as a pharmacist in a hospital in Java and that in 1825 he was sent from Java to Dejima of Nagasaki to become Von Siebold's assistant. In March of the year following his arrival in Japan, Bürger was granted the opportunity to travel to Edo, when, as a secretary to Von Siebold, he joined the Dutch embassy on its customary visit to the Shôgun in Edo. The embassy left Nagasaki in February 1826 and arrived in Edo at the beginning of April. After staying in Edo for forty days, the embassy returned to Nagasaki in the second half of May. Both on the journey outward and back Bürger helped Von Siebold in taking meteorological observations and in collecting minerals, animals and plants.