I was posting in an earlier post about these books that where published by John Deere. They where given to schools and colleges for free. I have several of the editions. They where published from 1927 to 1957. There are 28 editions. I find the older ones to be very interesting. The early editions also go into great detail on adjusting and using horse drawn equipment I also have used the later ones to learn more about adjusting tractor drawn implements. The main one being moldboard plows. These books where written when plowing was very important. I think that these would be a big help for many of the first time equipment users we have on here. The books are talking about the time many of our tractors where being used in everyday use. I just bought the 28th edition last year on E-bay for $20 including shipping. So they can be found very reasonable. Also many libraries have them too. They where originally written to be educational class books. I have attached a link to more about them.
Green Collector article about the books
Green Collector article about the books