This is/was a four volume set - Executive Edition" - published by Collier and Sons around 1900 (no exact pub date inside) shortly after the original 14 volume set was published by Scribner's ... and after Putnam also put out a set. See the table of contents and Preface for details. Blue cloth binding hardcover.
These 4 volumes contain the whole "Winning of the West". I have just located a set of the original 14 Volumes (whoa .... sticker shock!). It is on the way and I will see what I can figure out once it arrives.
The 4 Vol set is in very good to fine condition. Yes, page foxing and the color in the Volume Numbers on the spine is gone, but otherwise tight and free of any markings.
The single volume - Vol. 1 of Winning of the West has some faults- binding loose but pages all intact (stitched and bound). Pages have some foxing but not overly brittle. Former library.