The museum was given the status of a national museum during the period of P. E. P. Deraniyagala. He opened branch museums in
Jaffna,
Kandy, and
Ratnapura and a fully-fledged department of national museum was established in 1942 under the act No. 31. Nine branch museums were ultimately opened, and a school science programme and a mobile museum service are also in operation. The museum has a copy of the
Statue of Tara, a three-quarter life size statue of
Tara currently held in the
British Museum. The crown jewels and the throne of the last
King of Kandy, which were returned to Sri Lanka by the
British Government, were added to the museum collection. Ground floor galleries are arranged in historical sequence, and upper galleries thematically. A library was also established on 1 January 1877. The government
Oriental library (1870) was incorporated into
Colombo National Museum library, and served as the nucleus of the library collection by collecting the local publications of the past 129 years; the library has been functioning as an unofficial national library in Sri Lanka, and became the first legal deposit library in the island. From its inception, special attention was given to building up of a collection related to Sri Lanka, Orientation and Natural Science. In 1982 Dr.
Thelma Gunawardena became the first woman director of the National Museum of Colombo. She served from 1982 through 1994. From 1972 to 1991, Prof.
Pandula Andagama was the assistant director of the Department of Anthropology in the museum, and the assistant director of the National Museum. ==National Museum Library==