Unanswered Questions

An early photo of the Missisquoi Pulp & Paper plant in Sheldon Springs on the CV's Richford Branch. 

Researching railroad history can be a rewarding and fascinating past time. 
As a rule, historians focus primarily on "macro" examinations of their subject. And railroad histories for many years were the realm of classic economic or business historians. I remember reading the railroad books in the local library when I was a kid. You know the ones, page after page of board meetings, earnings, revenue and (mostly) losses. The one thing they all had in common were the "plates" in the middle of the book where there might be a photo or two of a train hidden among the portraits of the railroad's presidents. 
But even those type of histories seem to fall out of favor about the time the railroads were going into the toilet - basically the late 1960s. Frankly today most of the work in railroad history isn't been done by "professional" historians but by amateur historians. Whether this constitutes "real" history is a question I'm not going to touch. 
Historians who subscribe to "Cliometrics" - basically the application of statistical methods and analysis to history - tend to study industrial and transportation history. As a rule the more data, the more valid the resulting statistical analysis will be.  And large industries, such as railroads, have generated a lot of data that Cliometricians, as they call themselves, love to chew on. 
Back in my grad school days I took a business history class. My paper for that class was a look at the effect of the railroads that would eventually become part of the CV's southern division had on several "sub regions" of New England.  In doing the research I turned up some fascinating and obscure references - including a paper on the economic impact of the Amherst & Belchertown Railroad (told you it was obscure!) published in the early 1930s that Bernie Kempinski obtained for me from the Library of Congress. 
As we were packing up stuff this spring I came across my old paper and flipped through it. I realized two things: First of all, the paper really was pretty good, with a sound premise and valid research to back up my thesis.  
Second, and more to the point, there's little or anything that would be of use to a modeler attempting to duplicate those lines. 
Instead of focusing on the macro, modelers, and amateur rail historians, tend to focus on the micro. 
As I'm researching certain elements of the Richford branch I've come up with several questions I've been unable to answer such as:

1. I know the motive power used on the branch in the 1950s and later. I'm having difficulty determining which engines ran on the branch prior to that time. 
2. The Enosburg Falls station was an interesting building with some intricate trim. I can't determine when the structure was torn down. 
3. The Missisquoi Pulp & Paper Co. had it's own in-plant railroad, complete with a small engine house. I know they used a Track mobile to move cars around in the plant in later years. What, if anything, came before the Track mobile? 
4. I've located a couple of vintage images of the paper mill buildings, but would like an overall shot of the "river" side of the mill taken in the 1940s/50s - something more current than the one shown above. (see update below)
5. How was the Canadian Pacific interchange traffic at Richford handled? Did the Richford local bring those cars to the CP yard? Or did the CP come to the CV's yard to fetch them? Or is it something that changed over time? 
6. Did anyone ever take a photo of the Richford plywood plant from the CV yard during the time period I'm modeling? I've seen one photo that appeared in Ed Beaudette's book. the only other image is a quick glimpse in a "CV in Steam" DVD from A&R Productions. 

I'm noticing a trend in the information I have been able to uncover. Most of it seems to be from an earlier era than the 1950s. Does that mean an era shift is afoot? Don't know - ironically, I can't find a lot of railroad photos from earlier than that time period on the branch - a few, but not many. 
Somewhat frustrating is the fact that the vast majority of my reference material is in storage at the moment. Since I didn't start researching the branch in earnest until a few months ago it's entirely possible the answers to my questions are buried in the storage containers. 
In meantime, I'll do what I can and and keep piling up the questions.
Finding the answers is a lot of the fun of prototype modeling.

UPDATE: 

Scratch #4 off the list above. It's too cold to go out for lunch so I spent my lunch surfing - I stumbled across this photo on the UVM web site showing the Sheldon Springs paper mill. Look closely in the area of the mill in front of the hillside in the closeup image below and you can see the tower and horizontal covered walk visible in the vintage photo above: