He spent most of his life in Papua and New Guinea, where he worked as a civil servant and served as an official member of the Legislative Council.

[1] He left school at the age of 14 to work as a grocer's boy at the British New Guinea Development Company shop.

[1] Having walked from the north to the south coast of New Guinea alone following the Japanese invasion, he helped prepare Australian soldiers for the Kokoda Track campaign.

[1][2] In 1943 he transferred to the Australian Imperial Force, and in early 1944 was given responsibility for Lakekaum district, before taking over the administration of a much larger area later in the year.

[1] Following the war, Grahamslaw rejoined the civil service, becoming Superintendent of Stores and then Assistant Collector of Customs in 1949.