nga-tu

Lastly, the Western Australian and the Kowrarega so closely agree in the use of the numeral two for the dual pronoun, that each applies it in the same manner. Singular : nga-tu = I, me. Dual : albei = we two, us two. Plural : arri = we, us. Here the plural and dual are represented not by a modification of the singular but by a new word; as different from nga as nos is from ego.

John MacGillivray - Narrative of the Voyage of H.M.S. Rattlesnake, Commanded By the Late Captain Owen Stanley, R.N., F.R.S. Etc. During the Years 1846-1850. : Including Discoveries and Surveys in New Guinea, the Louisiade Archipelago, Etc. to Which Is Added the Account of Mr. E.B. Kennedy's Expedition for the Exploration of the Cape York Peninsula. By John Macgillivray, F.R.G.S. Naturalist to the Expedition. — Volume 2

The pronouns in question are compound rather than simple; i.e. instead of nga = me, and ngi = thee, we have nga-tu and ngi-du. What is the import and explanation of this? I hazard the conjecture that the two forms correspond with the adverbs here and there; so that nga-tu = I here, and ngi-du = thou there, and nu-du = he there. Eyre gives the double form ngai and nga-ppo each = I or me.

John MacGillivray - Narrative of the Voyage of H.M.S. Rattlesnake, Commanded By the Late Captain Owen Stanley, R.N., F.R.S. Etc. During the Years 1846-1850. : Including Discoveries and Surveys in New Guinea, the Louisiade Archipelago, Etc. to Which Is Added the Account of Mr. E.B. Kennedy's Expedition for the Exploration of the Cape York Peninsula. By John Macgillivray, F.R.G.S. Naturalist to the Expedition. — Volume 2