He then returned to Batavia and worked at the Museum of the Royal Batavian Society of Arts and Sciences (today the National Museum of Indonesia), and catalogued the museum's large collection of Javanese texts, accumulated over nearly a century.
Afterward, he went back to Batavia where he worked at the Museum of the Royal Batavian Society of Arts and Sciences (renamed as the National Museum of Indonesia). There, he compiled the large number of Javanese texts in the museum's collection, which had been gathered over nearly a century.