First I will re ask about the oil flowing in the winter. Did it have to be heated to be able to flow or was the temp hot enough that it flowed easily reguardless of the outside temp?
The manner in which Hughes kept the crude sufficiently fluid to allow for winter pipeline transit was a unique accomplishment using creative ingenuity. It is my understanding that the Gramps crude had a high asphalt component thus was somewhat thick upon extraction, but what is remarkable is that much of the pipeline route, even the portion crossing the Continental Divide was above ground, where it was exposed to winter temperature elements.
The crude likely acquired some heat capture from the pumping process to get it from the well heads to the apex of the Divide, but the downhill journey to Chama was powered strictly by gravity.
Apparantly during early operations, Hughes & Co. found that the crude was too thick to flow during the winter months. Accordingly, rather than incorporate infrastructure to heat the product, the Gramps folks decided to insulate, by incapsulating several miles of the line in wooden pipe runs containing saw dust. Lumber operations were still going strong in the area and the saw dust was no doubt free for the asking.
The pipeline ran near Rich Muth's property and I know he did extensive research on the enterprise. Perhaps Rich can share some findings and perhaps even some photos of the pipeline