I don't have Roy's books but the few I have tell some things and leave some things out.....on purpose?...maybe ....so they can
write another book.....
You have to be able to read between the lines and put 2 and 2 together and study everything on your maps! Everything means something and if you look hard enough and put your thinking cap on, you will figure it out.....What I have found is.....creeks on maps are not always creeks, same for trails....trails may be creeks....Dates will be more than dates......say for example the
date 1844.......it may mean the "1" is on a survey grid line of plat map, the 844 may mean 844 chains, varas, feet, etc.to a plat map grid line or marker in field or it may mean 1+8+4+4=17=1+7=8 , 8 may mean a "H" or "Foot print"
Got to love puzzles and have a knack for making things work in the puzzle. I have even take a magnifing glass to stare at marks on a map to finally see that that mark made a number that could barely be seen....and that number will be the biggest clue and the smallest mark....
If you have solved your map correctly, then all the indicators, Dates, lines, words, numbers etc, will all make sense TOGETHER and put you in the right area. Man made it and man can decipher it.