The Central Hospital Simeloengoen was established by the Rubber Plantation Investment Trust at Pematangsiantar in the hospital ressort of Siantar. Sources: van de Velde: “Het hospitaalwezen op Sumatra’s Oostkust”, Het Ziekenhuis, 1918. Legend of the central hospitals nr. 25. Mededeelingen Pathol. Lab.no 9, 1929: 7695 indentured labourers of whom 36 died. See Catalogus Hygiene Tentoonstelling Bandoeng 1927. See Grote Atlas van NOI, p. 104/105.
Simeloengoen and the Karolands: department of the Government of the East Coast of Sumatra, administrated by an assistant-Resident, residing in Pematangsiantar, a town of 15,000 inhabitants of whom 300 Europeans and 5,000 Chinese. The department Simeloengoen and the Karolands had almost 373,000 inhabitants, among whom 1,900 Europeans and almost 16,000 Chinese (Gonggryp 1934, 1297-1298).