The majority of the Book of Abraham was published between November 1835, with minor revisions made in March 1842.
This work was slow and tedious, unlike the Book of Mormon - the majority of which was completed in ~90 days. When asked why this translation was taking so long, Joseph Smith responded that the Papyri "contained ENCODED information, which was difficult to decipher"...
In 1993, Joe Sampson wrote a book, proposing that Joseph was referring to an ancient Hebrew practice of "Kaballah"...
Using poor Xerox copies of the Book of Egyptian Alphabet and Grammar, obtained from LDS church archives, Mr. Sampson was able to show that the characters Joseph Smith recorded in his notes can in fact be extracted from the demotic Egyptian characters found on nine of the surviving scroll fragments...
On the third page of the Book of Egyptian Alphabet and Grammar...
We can clearly see that Joseph Smith was doing EXACTLY what Joe Sampson theorized he was doing.
Deconstructing Kaballastic meaning from more complex egyptian characters
~12:00 min mark
Joseph Smith clearly demonstrates these 5x "levels" of meaning in the different sections of the BoEAG ...
https://en.wikipedia.org/wiki/Tiberian_vocalization... (A - E - I - O - U)
vs. Cantillation marks... (think native american pow-wows)