ʻŌpūkahaʻia’s Grammar Book
Noah Webster (1758-1843) was the man of words in early 19th-century America.; he compiled a dictionary which became the standard for American English. Webster devised a method to help differentiate between the sounds of vowels and assigned numbers to various letter sounds - and used these in his Speller.
It seems Henry ʻŌpūkahaʻia used Webster's Speller in his writings and substituted the numbers assigned to the various sounds into his words. So, using Webster’s coding, to decipher ʻŌpūkahaʻia’s ‘k3-n3-k3,’ you substitute the "3" for "a" (that sounds like "hall;") k3-n3-k3 transforms to kanaka (man.) 3-o-le transforms to ʻaʻole (no;); l8-n3 transforms to luna (upper) and 8-8-k8 transforms to ʻuʻuku (small.)