The Dotted Line Nos 1-12 Inc. issued by the CaterpillarTractor Co. and intended solely for the help of those engaged in selling "Caterpillar" Tractors. Number 1 was released April 10th, 1927 through Number 12 released April 10, 1028. 6" x 9" about 315 pages Hardcover with no dust jacket. Green cloth with bright gilt lettering and decoration on the front cover and a bright gilt '1' on the spine. Moderate cover edge wear. A small gouge  on the bottom edge of the back cover. Water damage on the bottom tips of front and back covers. Ownership label signature and initials inside the front cover. Some soiling and a black ink blotch on the top of the page block. Some foxing on the few pages inside the back cover. Well, I see no overt evidence of water damage. Pages from page 35 in the last volume on have a heavy clay content. Many of those pages have stuck together because of the clay and must have been exposed to moisture. I have separated every one of these pages but, this is created some abrasions between those pages. There are only a few places where there is loss to either text or pictures and none of these places have a large (more than a part of an inch in diameter) loss. The worst will be photographed. No other previous owner markings. There are about six pages with corner bumps.  No tears, other folds or creases to pages. Binding is tight with no looseness to pages. Not ex-library, not remaindered and not a facsimile reprint. For sale by Jon Wobber, bookseller since 1978. KF06a

"I had one of Our chapter 18 members drop in recently and gave me to read, a book called 'The Dotted line " by Caterpillar Has a number 3 on the Arch Nos 25-33 on the Front . it appears to be a series of Salesmen's Guides going back in the twenties and may be early Thirties, condensed into one big Book [its about 2' thick ] Covers a multitude of Things , mainly refers to 10/15/20/30 and 60 type tractors and hundreds of manufacturers of implements that match to these Machines , maybe these were available through Cat. dealers . Covers just about anything a Farmer /Contractor / Council would Need . from blade attachments to winches for logging and Oilwell work , Russell grader attachments , Log wagons , Grain Harvesters ,etc,etc ." - https://acmoc.org/forum/discussion/the-dotted-line 

"Caterpillar Inc. traces its origins to the 1925 merger of the Holt Manufacturing Company and the C. L. Best Tractor Company, creating a new entity, California-based Caterpillar Tractor Company." -  Wikipedia