Symmon's Noongar Grammar
One reason is that apart from an abridged publication as an Appendix in the 1892 edition of Lawrence Threlkeld's Awakabal Dictionary, it hasn't been published since 1842. Another reason is that the only other comprehensive attempt at a Noongar Grammar is by Wilf Douglas in the 1960's. But I suppose the real reason is that it's just so damn interesting!
Charles Symmons was not greatly regarded in the colony at the time because he wasn't a gentleman and he was overlooked for the position of 'Protector of Natives' which went to Francis Armstrong. But Symmons learnt the language quickly and although he acknowledges George Grey as the source of some of his work. I suspect that Grey owed him a debt as well when it came to writing and understanding Noongar language and culture. But then Charles wasn't a gentleman.
He was a teacher though and he had learnt Latin. So he established the first school for Noongar children. His knowledge of Latin is evident in his grammar and Latin wasn't a bad start when it came to Noongar.
Anyhow, you can take a look at Charlie Symmon's work at my Noongar language pages. I'm off to bed.